 -- THIS IS A RUSH TRANSCRIPT FOR 'THIS WEEK' on May 28, 2017 and it will be updated.

(BEGIN VIDEO CLIP)

ANNOUNCER: Starting right now on THIS WEEK with George Stephanopoulous.

DONALD TRUMP, PRESIDENT OF THE UNITED STATES: I think we hit a home run no matter where we are.

ANNOUNCER: After Trump's whirlwind trip.

TRUMP: Congratulations, great job

ANNOUNCER: The president back in the U.S. The Russia investigation still looming large over the White House.

UNIDENTIFIED MALE: Did evidence exist of collusion, coordination, conspiracy?

ANNOUNCER: And new revelations of Jared Kushner, one of Trump's top advisers.

UNIDENTIFIED MALE: This is off the map. I know of no other experience like this in our history.

ANNOUNCER: The very latest on this breaking story from Jonathan Karl and Pierre Thomas. And our exclusive with the top Democrat on the House Intelligence Committee, Adam Schiff.

Plus, after a devastating attack --

TRUMP: Terrorism is a threat, bad threat.

ANNOUNCER: What are the security threats here at home? Tough questions ahead for Homeland Security Secretary John Kelly.

And what makes Trump tick?

UNIDENTIFIED FEMALE: Were you surprised that he's not different in office?

ANNOUNCER: Insight and analysis from our panel of experts.

From ABC News, it's THIS WEEK. Here now, co-anchor Martha Raddatz.

(END VIDEO CLIP)

MARTHA RADDATZ, ABC HOST: Good morning on this Memorial Day weekend. Americans welcoming the summer and paying respect to those who have fallen defending our freedom.

We'll have the story of a missing marine and his son's long quest to bury him with honor later in the program.

But we begin with the deepening political crisis over the Russia connection, to all the investigations, all the dramatic headlines, all the shifting stories about Russia's election interference and the Trump campaign's possible role in it. The president has been clear about one thing, consistently saying that he never colluded Russia to alter the course of the presidential election.

And let's be clear: he's right. We've seen no evidence of collusion between Trump and Russia during the campaign. But what we do have this weekend is a new shadow of suspicion now falling on Trump's most powerful, closest, and most influential adviser -- his son-in-law, Jared Kushner.

"The Washington Post" headline: Russian ambassador told Moscow that Kushner wanted a secret communications channel with Kremlin. "The Post" reporting Kushner wanted to use Russian equipment and Russian diplomatic facilities. That one quickly followed by "The New York Times": Kushner is said to have discussed a secret channel to talk to Russia.

ABC News has confirmed that Kushner did indeed meet with the Russian ambassador last December to talk about setting up a private back channel. Sources stressing that the conversation with the president's son-in-law was focused on the U.S. response to the crisis in Syria and other policy-related matters.

While that may be true, pause for a moment to consider the context here. We know from the U.S. intelligence community that Russians meddled in the U.S. election with the goal of weakening Hillary Clinton and propping up Donald Trump. We know that after Trump's victory, Russia was politically poison, a hostile power accused of undermining the foundations of our democracy.

So in that environment, Jared Kushner's actions were at best highly unusual. And while his actions do not prove the election collusion that Trump has repeatedly denied, there are three congressional committees, the FBI, and now a special counsel, all intensely looking at every single allegation of impropriety -- every one opening up the possibility of new subpoenas and more people interviewed under oath.

And as the allegations now focus on the president's own son-in-law, a man whose West Wing office sits just feet away from the Oval Office, the risk to the president gets ever more serious.

So let's bring in our chief White House correspondent Jonathan Karl, just back from the president's week-long trip overseas, and our senior justice correspondent Pierre Thomas, who covers the FBI and Justice Department.

And good morning to you both. And, Pierre, and I want to start with you. There have been revelation after revelation for weeks, but this seems to really raise the stakes. What are your sources telling you?

PIERRE THOMAS, ABC NEWS SENIOR JUSTICE CORRESPONDENT: Martha, high stakes are on the horizon, no doubt about it. This revelation that Jared Kushner was in communication with Russian officials, the ambassador and a Russian banker, is huge. And the FBI wants to know some basic things -- why was it urgent to have that meeting? Why was it -- there a discussion of having these back channels? And, again, the context is that this is after the intelligence community has said the Russians were meddling in the 2016 election. Lots of questions. There's no allegation yet that Kushner has committed any crime. He's not a target of the investigation. But the FBI is coming soon and they want to know what he knows.

RADDATZ: And Jon, this comes after this week long trip, which the White House considered very, very successful.

KARL: Sure.

RADDATZ: But now they're back to this investigation. I was struck by the CIA director, former CIA Director Mike Hayden, who made them this week about the Kushner contacts. He said, "What manner of ignorance, chaos, hubris, suspicion, contempt would you have to have had to think that doing this with the Russian ambassador was a good or appropriate idea? I know of no other experience like this in our history, certainly within my life experience."

An incredibly strong statement from Hayden.

KARL: Yes. And, you know, he's been a Trump critic for a long time, General Hayden, but he's former head of the NSA, former head of the CIA. Few people alive today know the intelligence world better than Michael Hayden.

So make no mistake, when you hear those words from him, you know that those are views that are reflected by senior people currently in the intelligence community.

The bigger question, though, Martha, is what about Jared Kushner's role?

As you mentioned at the top of the show, there is no adviser closer to the president -- his office goes -- opens right into the Oval Office. He has taken on a portfolio bigger than anybody in the West Wing. And you see -- you hear people now very close to the president openly saying that it is too much, that he now finds himself at the center of this investigation, even if he is ultimately completely cleared, he is at the center of this investigation right now.

And you hear people close to the president quietly saying, is it too much and is it time for Jared to take a step back, maybe even take a leave of office -- leave of absence from the White House.

RADDATZ: And do you think that's something that President Trump would agree with?

KARL: Well, you know, Trump is looking for -- you know, there's a lot of -- there's talk of a major shake-up coming. We'll see if it actually does. There's been talk before and then he hasn't pulled the trigger.

But he has been upset with how things have gone. He has reached out, I know, to people outside of the White House for advice on what he should do.

Should he bring new -- more people in?

Should he move anybody out?

I think that will be some form of a shake-up coming. I think that -- who knows?

Like all things are on the table with Jared Kushner.

But the communications job, whether or not we'll ever see a Sean Spicer briefing again, I think these are all open questions right now.

RADDATZ: And Pierre, on the investigation, where does this go now?

We know former FBI Director Comey is supposed to testify publicly.

Do you know when that will happen?

What are the next steps here?

THOMAS: Martha, in a week of dramatic moments, perhaps the most dramatic moment was when the former CIA Director Brennan said that he had evidence that Trump associates were communicating with Russian officials.

Now you have a special counsel who is going to get to the bottom of what those communications are about.

I'm being told by sources that Mueller, the former FBI director, now special counsel, is already working long hours. He's staffing up. He's beginning to assess the investigation.

And I'm told that he is going to get to the bottom of all of this, that everyone who's in Trump's orbit who had communications with the Russians are going to be interviewed and pressured.

And remember, every time that you speak to an FBI investigator when you're being interviewed, there's a threat of a federal crime if you lie to them. So everybody involved is going to face a lot of pressure.

In terms of Comey, the expected is that he will testify before Congress. We don't have a date specific yet. He wants to tell his story. From people that are close to him that I've talked to, he's heard all those accusations about him being a, quote, "nut job," people describing his actions as atrocious.

He is going to want to have his say.

RADDATZ: Thanks very much to both of you, Jon and Pierre.

And I'm joined now by Congressman Adam Schiff, the top Democrat on the House Intelligence Committee.

Good morning, Congressman Schiff.

REP. ADAM SCHIFF (D), CALIFORNIA: Good morning.

RADDATZ: Let's start with your reaction to reports that Jared Kushner tried to set up a secret back channel with the Russians.

SCHIFF: Well, of course, I can't confirm or deny whether they're accurate. But if they are, it's obviously very concerning. And as you said at the top of the show, it's all about the context. John Brennan testified this week that what concerned him wasn't simply that the Russians were having contact with people associated with the Trump campaign, that the reasons have contacts with Americans quite routinely.

But it was the context of an election campaign in which the Russians had been intervening to help Donald Trump, to hurt Hillary Clinton. And, of course, if these reports are accurate, right after that campaign, after that intervention, to have the president's son-in-law, a key player within the Trump Organization trying to establish a back channel with the Russians through a Russian diplomatic facility, you have to ask, well, who are they hiding the conversations from?

RADDATZ: Well, you're talking about context. So it would be OK if it was a back channel if all this other context hadn't happened? I know H.R. McMaster, the president's national security adviser, said he was not concerned about back channel communications. Historically there have been back channels.

SCHIFF: You know, I was disappointed to see the general say that. I have a lot of respect for him. Sadly I think this is an administration that takes in people with good credibility and chews them out and spits out their credibility at the same time.

Yes, that's true in the abstract what General McMaster said.

RADDATZ: You are saying he has lost his credibility…

(CROSSTALK)

SCHIFF: No, but I think that anyone within the Trump orbit is at risk of being used. And what the general said here, that may be true in the context where you're trying to arrange secret talks with the Taliban to negotiate a peaceful resolution or you're trying to achieve the release of hostages.

But for people associated with the campaign after that campaign has ended and where the Russians during that campaign were helping you, to try to establish a back channel and hide it from your own government, that's…

RADDATZ: The New York Times and…

SCHIFF: … a serious allegation.

RADDATZ: … ABC News have both reported that the talks were about Syria, about the crisis in Syria and other policy matters.

SCHIFF: Well, that I don't think necessarily mitigates this because, of course, the Russians have their own object in Syria very different than ours. They want to prop up Bashar al-Assad. Our policy, at least at that time, if these allegations are correct, was very much in opposition to the Russian policy.

And if American policy was going to change for the wrong reason, that is, as a thank you to their intervention in the campaign, obviously that's very problematic, just as problematic as it would have been if the conversation was on relief of the sanctions over Ukraine.

Now, again, this is all in the category of allegation, but it is something that our committee needs to get to the bottom of as well as Bob Mueller.

RADDATZ: Had your committee, can I ask you, seen any of this type of evidence at all up to this point with Kushner?

SCHIFF: I can't confirm or deny what we have seen.

RADDATZ: It was reportedly through monitoring of Ambassador Kislyak that this was discovered. Ambassador Kislyak has to know that he's monitored all the time. So could this be a ruse on the part of the Russians? Can you see any explanation why they would try to put this information out or get this information out or talk to each other thinking we'll think Kushner is involved but he isn't?

SCHIFF: You know, again, I don't want to comment too much beyond what is alleged here. You know, certainly in dealings with the Russians, they're very sophisticated. You always have to take into consideration that the Russians may be doing things that are designed to throw you off the track or provoke discord. They're very sophisticated. So I don't think you can rule anything out.

RADDATZ: Can you see a reason? It's confusing to me why they would do this. It was back in December, Jared Kushner was not in government yet. Didn't even have a security clearance.

SCHIFF: Well, you know, it's hard to understand, if these allegations are correct, why this would be some kind of a Russian ruse. Why would they want to undermine the very government that they hoped to have a good relationship with, the incoming Trump administration?

So I'm not sure you can see a motive for a ruse here. But, again, all of this is still within the category of allegation. I do think ultimately we're going to want Mr. Kushner to come before our committee. I fully expect that that will happen. I'm sure that Mr. Mueller is going to want to look into these allegations as well.

RADDATZ: Do you think because of these allegations he should stay in the White House right now?

SCHIFF: Well, you know, there is another question about his security clearance and whether he was forthcoming about his contacts on that. If these allegations are true and he had discussions with the Russians about establishing a back channel and didn't reveal that, that's a real problem in terms of whether he should maintain that kind of a security clearance.

RADDATZ: Should he maintain it now? I know the DNC says no.

SCHIFF: Well, I think we need to get to the bottom of these allegations. But I do think there ought to be a review of his security clearance to find out whether he was truthful, whether he was candid. If not then there's no way he can maintain that kind of a clearance.

RADDATZ: You know, this also came around the time that Kushner was reportedly looking for refinancing into one of his companies, buildings on Fifth Avenue, and that he also met with an executive of a sanctioned Russian bank. Is that an issue?

SCHIFF: Well, it is an issue. And, of course, one of the things that the Russians do, and this is also in the category of allegation at this point, is they financially entangle people and they like to do business with business people because they think they can exert economic influence over them in a way that will shape policy.

So if that was what happened here or what was going on here, yes, it would be of deep concern and that's something we need to get to the bottom of.

RADDATZ: There have been an extraordinary number of leaks since President Trump became president. Is that a reason that Jared Kushner, if the allegations are true, might have gone around and tried to back channel so it wouldn't leak?

SCHIFF: I don't think that would be a motivation here. To me that would be -- require a certain roundabout thinking that doesn't make sense, doesn't resonate with me.

But you're right, I think leaks are an issue. They're an issue for every administration; they certainly are an issue for this one.

If this material is accurate, these allegations are accurate, it represents another serious leak. And that's a problem.

There really have been a couple categories of leaks, one that have been potentially disclosed sources and methods -- those are the most troubling because it could dry up very important information for the U.S. government. The others are in the category of exposing malfeasance and sometimes they overlap.

But, yes, we need to do everything we can to make sure that we're protected our sources and methods.

RADDATZ: Let's move to the investigation in the House. What is the mandate of your committee's investigation? What -- if it's a fact-finding mission, what kind of action is possible? How do you prove intent? Could ignorance of the law clear somebody?

SCHIFF: Well, ignorance of the law is an issue Bob Mueller will have to address, because he's going to look into whether charges should be brought, and if so, against whom. Our responsibility is really very different. Our responsibility is to try to figure out what happened. What did the Russians do? How did they do it? Did they use U.S. persons in this? What was the U.S. government response? And ultimately our most important responsibility is to tell the public what we learned, tell the public what steps we're recommending to be taken to prevent this from happening again.

So in that respect, what the intent was, we'll want to report to the American people, but it doesn't disqualify our concerns about it. It will have its greatest impact on whether a case is prosecuteable. But our job, really, is one of informing the public and taking steps to protect the country.

RADDATZ: "The Washington Post" reports that the Gang of Eight was recently notified of a change in tempo and focus in the FBI investigation. If the pace of that investigation is increasing, does your committee need to take a step back?

SCHIFF: Well, that's a very important question and I think the answer is no. We have two very different responsibilities. Before Bob Mueller was appointed, we had a different contact at the Department of Justice to deconflict. So questions like immunity for Michael Flynn. We obviously want to talk to the Justice Department and find out what are their prosecution equities here. That party's now changed; it's Mueller instead of Rod Rosenstein. But our fundamental mission hasn't changed, and indeed, if you look at Rod Rosenstein's memo about the firing of Comey, his primary criticism was that Comey talked about the investigation at the time he closed the investigation back in July.

What that means, because Mueller still works for Rosenstein, is that when Mueller is finished, if Mueller doesn't bring charges, Rosenstein's going to tell him not to talk about it at all. Why he didn't bring them, what he found, what he didn't find. If he brings charges against some but not others, he's not going to be able to talk about why he made those decisions.

That's going to be our responsibility, to inform the public and so that work really has to go on and it needs to go on in parallel. We need to deconflict where possible, but that work has to go on.

RADDATZ: And just one final question, does Congressman Devin Nunes still have a say on whether the committee issues subpoenas even though he stepped down as the chair of that particular probe?

SCHIFF: He does. I don't think that he should, given that he has stepped aside or recused himself. What I have been urging is that we have a committee vote. That's a procedure that's provided for in our rules. Or that the committee delegate to Mr. Conaway, with advice and consultation with myself. That's similar to what the Senate has done, and that's what I recommend we do here.

RADDATZ: OK, thanks very much for joining us this morning, Congressman.

SCHIFF: Thank you.

RADDATZ: Much more to come. Up next, after the president's first foreign trip, how will the White House respond to the latest questions on Russia?

And how safe is the U.S. after that attack in Manchester? I'll ask Homeland Security Secretary John Kelly.

And later, you probably know that President Trump is the first president in American history never to have served in public office or in the military. So how did he rise from New York businessman to the nation's highest office? And what does that rise tell us about how he'll respond to the crisis at home and abroad?

That discussion is coming up.

(COMMERCIAL BREAK)

(BEGIN VIDEO CLIP)

UNIDENTIFIED MALE: We stuck together in the face of those who seek to harm us and destroy our way of life.

(END VIDEO CLIP)

RADDATZ: Thousands turning out for the annual Great Manchester run today.

The race continuing despite concerns after that deadly concert attack this week. Runners taking a moment to pay their respects to the victims in St. Anne's Square, a show of unity and resilience.

And when we come back, the security fears here at home -- how is the U.S. guarding against the terror threat this Memorial Day weekend?

I talk to Secretary of Homeland Security John Kelly next.

(COMMERCIAL BREAK)

RADDATZ: We're back now with Secretary of Homeland Security John Kelly in his first THIS WEEK interview since joining the Trump administration.

Good morning, Secretary Kelly.

JOHN KELLY, SECRETARY OF HOMELAND SECURITY: Good morning, Martha.

How are you?

RADDATZ: Good to see you. I want to get to this breaking story. I know you don't want to talk about the investigation, but do you think back channeling is normal and acceptable?

KELLY: It's both normal, in my opinion, and acceptable. Any way that you can communicate with people, particularly organizations that are maybe not particularly friendly to us is a good thing.

And, again, it comes back to -- whatever the communication is, it comes back into the government and shared across the government. So it's not a bad thing to have multiple communication lines to any government.

RADDATZ: Using their equipment in their diplomatic facilities?

KELLY: Well, again, don't know all -- I don't know if all of that is true. I would just say that any line of communication to a country, particularly a country like Russia, is a good thing. And, again, it comes back into…

RADDATZ: Even using their equipment? I know you don't know if whether that's true or not. But…

KELLY: I would say any -- I mean, using their equipment, you know, that would cause you to be -- that communication would be considered to be, you know, kind of somewhat compromised. But the point is that any line of communication to a country like Russia is a good thing.

RADDATZ: Let me say, though, Kushner was not yet in government. Didn't have a security clearance. And was working potentially at cross-purposes from people who were still in office.

KELLY: Yes, I don't know that to be the case.

RADDATZ: And the Russians had just meddled in our election.

KELLY: Yes, I don't know that to be the case but the point is during the transition process, to open channels of communication with any country, back channel, up-front is a good thing.

RADDATZ: Even ones that meddled in our election.

KELLY: I would just say any line of communication -- I mean, you consider that as you interact with them, but any line of communication is a good thing.

RADDATZ: Why would somebody like Michael Hayden, who was director of the CIA, and I know he has been a critic of President Trump, but he knows a lot about these things, why would he say, as we said before, "what manner of ignorance, chaos, hubris, suspicion, contempt would you have had to have to think that doing this with the Russian ambassador was a good or appropriate behavior?"

Why are you so at odds with someone like that?

KELLY: Yes, you know, and Mike is a great guy, but I just say, any information flow into the government and then considered by the government, I won't criticize that. I don't think it's a bad thing.

You consider it in terms of whether it's reliable, but all of these lines of communication are, you know, a positive thing in my opinion. You just have to assume, like in this case with the Russians, that it's constructed in a way that they're trying to get you to do certain things.

But at the end of the day it's not a bad thing to have lines of communication across the spectrum.

RADDATZ: OK. I want to move to the U.S. threat level after the attack in Manchester. It is Memorial Day weekend. You say this week that we should expect a lot more attacks like the one occurred at that concert venue in Manchester.

Authorities are paying -- Homeland Security certainly paying more attention to these soft targets. But what can really be done at places like that to protect people? Don't they just move to the next soft target?

KELLY: They do. You just have to be vigilant. You know, it's trite but people should understand if they see something they should say something. Since I've been in this job 100 and I don't know 25 days, 30 days, I have called my counterpart in the United Kingdom three times to offer my condolences for terrorist attacks.

Three times, in 120, you know, days. This is nonstop. They are out there trying to hurt us every day. The good news is for our country that we have not suffered anything like this from external threats since 9/11.

That goes to the effectiveness of our military overseas, CIA, our NSA, and at home DHS, local law enforcement, FBI. But it's relentless, it's nonstop. They're trying to hurt us every day. We just have to be vigilant.

RADDATZ: You said something this week along those lines, you said, if you knew about terrorism, they never -- if people knew about terrorism they'd never leave the house. That is a very frightening statement. Are things getting worse?

KELLY: I wouldn't say worse. I would say the same. But, again, Martha, it goes to the issue of we have unbelievable men and women protecting us every day. You know, we talk about the 1 percent in the military. There's about another percent of people in law enforcement, DHS, FBI that are just -- they never sleep. We never sleep.

RADDATZ: What concerns you most right now, aviation?

KELLY: Aviation.

RADDATZ: And we have these airports testing out -- taking basically all large electronics out and putting them -- 10 airports including LAX, and why those particular airports?

KELLY: Well, because the TSA people that are looking at those bags as they go through the -- the scanner can't see exactly what's in the bag, so now -- because they're stuffed so full -- now in terms of the TSA process, they will ask people to open their bags so they can look inside.

So it has -- has to do with how much you stuffed in the bag.

RADDATZ: And just to be clear, I do want to go to the countries where laptops are banned. And that may spread to other points of departure -- Europe, possibly -- because of the threat.

KELLY: It could, but, you know, based on what we did on the 21st of March -- that's when I put that protocol in place -- every airport around the country is, OK, you know, what -- United States, Kelly, what can we do to raise the level of security so that we don't have to go in that direction? So I have an unbelievable cooperation of the Europeans, the Middle Easterners, the Asians. So we're very definitely going to raise the bar in terms of baggage security.

RADDATZ: And I just want to close on the matter of intelligence sharing. The British basically temporarily cut off intelligence sharing after the pictures of the device were shown in "The New York Times" and also the bomber's identity.

KELLY: Right.

RADDATZ: Your reaction to that and should those leakers be prosecuted?

KELLY: It's outrageous that that was leaked. I, as I mentioned before, immediately after the bombing, contacted my counterpart in the UK for the third time in 120 days, and offered our nation's condolences. And she rightfully then said thanks for that. Now, the leak. It's outrageous that those kind of things are leaked. I don't know why people do it, particularly when it's classified, particularly when it's ongoing. The event was still really ongoing. I don't know why they do it. It's just outrageous.

RADDATZ: I have to say that President Trump has constantly criticized the leaks as well, but he reportedly revealed some information to the Russians that came from Israeli intelligence. Former government officials who previously worked for George W. Bush, Eliot Cohen and Condoleezza Rice, called the act appalling. If accidental, it would be a firing offense for anyone else. If deliberate, it would be treason.

KELLY: Allegedly what the president said. That's my understanding that the White House has pushed back and said he didn't do that, so I'll take him at his word.

RADDATZ: On sources and methods, I think they've said.

KELLY: I should take the president at his word.

RADDATZ: OK, thanks very much --

KELLY: Thanks for having me.

RADDATZ: -- for joining us, Secretary Kelly.

KELLY: Sure.

RADDATZ: Good to see you.

When we come back, President Trump can often leave the public guessing at what he'll do next. So what really makes President Trump tick? I'll talk to three experts who've spent years charting the president's remarkable rise. That's up next.

(COMMERCIAL BREAK)

(BEGIN VIDEO CLIP FROM 1987)

TRUMP: I have zero political aspiration. I run a company. I believe I do it better than anyone. I enjoy what I do. I deal with all of the same people that we're talking about. I deal with the Saudis. I deal with the Japanese. I don't think anybody sells much more real estate than I do to the Japanese, the Saudis, etc. And I like the people. But that doesn't get away from the fact that this country is being totally ripped off by foreign countries, many of whom I deal with. And I think it's very unfortunate for the United States.

(END VIDEO CLIP)

RADDATZ: That was Donald Trump back in 1987, 30 years ago, denying any political ambition but sounding very much like the President Trump of today.

So how has the Oval Office changed the president?

Coming up, I'll talk to three people who have followed him closely and have special insight into what defines Donald Trump.

(COMMERCIAL BREAK)

(BEGIN VIDEO CLIP)

TRUMP: You know, coming from a different world and only being a politician for a short period of time, how am I doing? Am I doing OK? I'm president. Hey, I'm president. Can you believe it, right?

(END VIDEO CLIP)

RADDATZ: Yes, he is. That was President Donald Trump in the Rose Garden after the house health care victory, seeming to relish his remarkable rise to the White House. And on this holiday weekend we wanted to take a step back and talk to some of the people who followed Trump through the years.

Was his rise to the Oval Office predictable? What does his past tell us about what Trump's future holds? I sat down on Friday with Gwenda Blair, author of "The Trumps: Three Generations of Builders and a President," the definitive family biography of Donald Trump. Timothy O'Brien, author of "TrumpNation: The Art of Being the Donald," which takes a close look at Trump the businessman. And our Tom Llamas, who covered the historic Trump campaign every step of the way for ABC News.

(BEGIN VIDEOTAPE)

Gwenda, I want to start with you. You have known Donald Trump for how many years?

GWENDA BLAIR, AUTHOR, "THE TRUMPS": I started working on my book in the late '80s.

RADDATZ: And how do you think he has changed?

BLAIR: Not a bit. Not a bit. He is exactly the same guy. He has been doing the same thing for 40 years and it works. He has got that laser focus on the market or now on -- over the campaign on the voters, what do they want to hear? That's who he is. He's a salesman. And his best product is himself and he's really good at selling it.

RADDATZ: And, Tom, you covered him every single day on the campaign. I don't think you really knew him before but you saw him right away do exactly what Gwenda is saying, sell himself. Do you think he changed or are you surprised that he's not different in office?

TOM LLAMAS, ABC NEWS CHIEF NATIONAL CORRESPONDENT: You know, he's 70 years old and for the better part of his adult life he has never had a boss. He has always been the boss. So he has never had to listen to anybody. He has never had to really evolve in his views.

And right now, I don't care how great of a tactician, how brilliant of a political scientist walks into that Oval Office, whatever they tell Donald Trump, he's going to do what he wants to do. And that's what he did through the campaign.

And I agree with your point, he is his best spokesperson and that's maybe the only part of his presidency so far that has hurt him is that he has had messengers come out, whether it be Sean Spicer or Sarah Huckabee Sanders, the best salesman for Donald Trump is Donald Trump.

He's always his best mouthpiece. And I think by taking him away from the press, by having lack of news conferences, that's not Donald Trump. Donald Trump loves a camera.

I remember the campaign trail, we could be anywhere and the staff would say no interviews, he's not talking to you. As soon as he sees that camera and that red light turn on and a microphone, he makes a beeline to you.

It empowers him. I think it actually strengthens him. And it's something he's good at. And I think they're doing a disservice by keeping him away from the cameras.

TIMOTHY O'BRIEN, AUTHOR, "TRUMPNATION": I would depart from Tom on the notion though that if they let Trump be Trump that's the best thing to do because he's a good spokesman for himself.

I think he's a good source of energy on the campaign trail. It's why he got so much attention. He's this force of nature. And he's uninhibited. He's essentially Mr. Id. And he runs around saying whatever is on his mind. And he loves being on the campaign trail when he can be the source of attention.

The second he's not, he -- it's like a vacuum is lifted out of the room.

BLAIR: I'm not sure that it's -- he is his best salesman but I think there's also something to having those spokespeople out there and then he can jump in and be the distraction from whatever it is that they said.

So he has got this kind of perpetual motion distraction story, distraction story, distraction story, distraction story, distraction, so he has got us all covered. If it was just him, you know, he wouldn't get that thing, that tension of that back and forth distraction story, distraction story.

LLAMAS: I think some people sometimes put too much into this, oh, it's all Trump's strategy, it's his grand plan. And I think what he loves about the cameras, what he loves about the TVs, he's a man that doesn't have vices. He doesn't retire at night with a cigar. He doesn't enjoy a nice glass of scotch.

What he loves is getting in front of that camera and just grappling with reporters and going back and forth. I used to see news conference that would be half hour, hour long, where he was just getting nailed with tough question after tough question, and he would finish and he would be in a good mood.

And any other politician would be demoralized, but he was OK with it.

RADDATZ: But when I look at the past few months, the past four months, and you look at some of the things that President Trump has done, this is a man who watches cable a lot. He watches the Sunday shows. He is aware of everything that's going on, on the air.

And yet, didn't seem to understand that firing James Comey would be a big problem on both sides of the aisle, even though he watches television all the time, even though he, you would think, absorbs how it's covered, that seems to be an area that they are not very good at.

O'BRIEN: But I don't think he absorb media strategy. His strategy is to be in front of a camera. It sort of begins and ends there.

LLAMAS: And he reacts. He doesn't respond. So whatever that spur of the moment decision is, he'll do it and it's very hard to talk him out of things. I mean staffers who know him, who have been with him for years say that it's very hard to talk him out of things.

You have the Comey firing but you also have -- when he announced the tax plan, and that caught his staff by -- like completely by surprise. He said we're going to have it next week, something to that effect. And they weren't ready with it.

It turned out it was one page long.

RADDATZ: So if you were on his staff and you wanted him to listen to you, what would you do, having watched him all these months and years?

What would you do if you were a staff member to try to give him advice that you just knew he had to take, that you just thought was so important?

LLAMAS: You'd play to his ego. I'm not that -- that's the only way that I think you can get things through to him. I mean in a lot of ways, I think some politicians here and in Washington have understood a way to get through to him is to compliment him. And that's a way into Donald Trump, because the one thing you can't do with him -- and I know this very well -- is you cannot criticize him, because if you ask a question or you criticize him publicly, he's at war with you.

RADDATZ: And you have personal -- he called you a sleaze.

LLAMAS: I asked him a tough but fair question, if he had a problem with the truth, that sometimes he exaggerated things. It was during that news conference when he had mentioned he had raised $6 million for vets in Iowa. It turned out that was not the case.

And I asked him, I said do you sometimes stretch the truth?

Your critics say, you know, you have a problem with the truth. And he got really upset and he called me a sleaze.

He got over it, but he's very thin-skinned.

RADDATZ: Tony Schwartz, who wrote "The Art of the Deal," who has been talking quite a lot about Donald Trump over these months and years, says he sees a sense of self-worth that is forever at risk.

O'BRIEN: I think that's totally true.

RADDATZ: Where does that come from?

I know one of the things that people will say is it's his father.

You met his father.

BLAIR: A tough guy, that dad. Relentless, ruthless.

O'BRIEN: Yes. Yes.

BLAIR: He worked 24-7, took the kids around to building sites...

O'BRIEN: To collect nails.

BLAIR: To collect nails. Yes.

Why would you waste that?

He was always looking for a way to save an extra dime. Last minute, any kind of negotiations, signing a contract, dad would stop it and chisel off a few more cents. Tough as nails.

RADDATZ: I want you to tell me this story about Palm Beach. You have an anecdote in Palm Beach that you should told you a lot about Donald Trump.

O'BRIEN: The president and I flew down to Palm Beach on his jet from Manhattan. This was in around 2005, with Melania. We had dinner together.

And during the day, he had taken me around Palm Beach in his Ferrari. And he would put the window down at stoplights and he'd say watch what happens.

And then the window would come down and people would point at him from the sidewalks or from the cars. Then he'd put the window back up.

Anyway, we had dinner that evening and afterwards, we were standing by the pool and there were probably a dozen speakers that were almost as big as me, six foot speak -- six foot high speakers. And Donald was cranking classic rock and really loudly.

And I'll have to -- the -- he swears quite a bit, so I'll tell this story, I think, in a clean TV safe way.

But he leaned over to me at one point and he said, you know, when I moved here to Palm Beach, nobody wanted me around. And I love cranking this music as loud as I can because it bugs the heck out of all of these so and so and I love it.

And I think that, you know, he didn't have to go to Palm Beach. So the interesting thing here is he chose to go to WASP heaven and buy an estate there. And -- but then he got there and he rejected the norms of WASP heaven.

And I think that that's explanatory of a lot of motivations in his life. He wanted to get out of Queens to come into Manhattan. He wanted to be accepted by the real estate class in Manhattan, but then he thumbed his nose at them.

He wanted to run as president as a Republican. I think part of him wanted the Republican establishment to approve him, at the same -- in the same breath, I think he thumbed his nose at the Republican establishment.

And I think that little moment by the pool in Palm Beach speaks to all of that.

BLAIR: I had another experience with him in Palm Beach that was earlier. This was in the '90s. And it was in West Palm Beach, which is, of course, not the swanky part.

When condo towers that he had bought and he put his name on them, of course, and tried to sell apartments in them, the bank foreclosed. These units were put up for auction.

You might have thought that it was an embarrassing situation. Not for him. He walked around the auction, chewing on Tic-Tacs, greatest day of his life, telling everybody that this was a marvelous opportunity, they would be really happy. It was going to work out great for everybody, no problem. It was all terrific. And I was just sort of dumbfounded.

RADDATZ: I want to move to Ivanka Trump. He clearly has a close relationship with her. He clearly admires that young woman. What do you think of that?

LLAMAS: You know, he comes from a family business. I think that's the only way he knows how to do business, and I think he feels very comfortable with having a relative in there. Because I think he knows, at the end of the day, as loyal as some of his staffers are -- and he has staffers that are much more than just employees. mean they essentially are family to him too.

But blood is thicker than water, and I think he always needs to have someone there. And in his eyes clearly he sees Ivanka is the heir to the Trump dynasty. His sons did a great job during the campaign ;they're running the business right now. I just spent some time with them. They're staying busy. But Ivanka clearly is the heir to the throne. He wanted to bring her in.

And it's like any other business deal. If she can learn something from this, he's going to bring her in and she's going to help him and she's also going to learn some experience too.

RADDATZ: I want you to tell me what you think the best part of Donald Trump is. What's great about Donald Trump? What is good about Donald Trump from what you've seen?

LLAMAS: I'll say this, and it is -- I believe this to be a true testament of how people are elected. They always say the beer test. Would you want to have to a beer with this person? And even though President Trump doesn't drink, he is a lot of fun. He is funny, he's charismatic, and if it was in a small group or an audience of 30,000 people, he wants to be liked and he works hard to be -- to want to be liked.

So one on one it's hard not to like him. I think his humor, his optimism, are definitely his strengths.

O'BRIEN: I think he's a survivor. I think people have always underestimated how tenacious he can be. I also think there's a Jekyll and Hyde element. He's a very different person I think one to one when he's out of the public eye. He can be actually a pretty good listener. He can be very open to talking about almost anything, which is part of the entertainment value with him. But that transforms when he gets out on the public stage.

BLAIR: He wants to win. There's a certain possible flexibility there. He'll reframe it and move it around and turn it upside down, but at the end of the day, he wants to win. And so he will be flexible on things. He's kind of practical, finally. He wants to make it work out. And he doesn't want to lose.

RADDATZ: Will he run again?

LLAMAS: I think so. I mean, I think he -- I think the best part for him as far as enjoyment, was the campaign. I think he loves going to those rallies. It's the closest he can be to a rock star. He walks in, the music's blaring, the people are cheering for him. All those people there to see him and he loves that.

O'BRIEN: I think he'd like to be president of life, if the world allowed it. I could see him running four or five more times. I think he has no intention of going away.

Reality, some investigations, the electorate all might intrude, but I don't think he thinks about it that way.

LLAMAS: He did say that he would only need one term because he'd fix the country in four years.

(LAUGHTER)

LLAMAS: He did say that on the campaign.

O'BRIEN: That's right.

RADDATZ: Gwenda?

BLAIR: Absolutely. He's the most competitive guy who ever lived, and this is the biggest gold ring there is. He's got it in his hand; why would he let it go?

(END VIDEOTAPE)

RADDATZ: And he is already tweeting again this morning.

When we come back, one family's moving Memorial Day story honoring a Marine missing in action for decades in Vietnam.

(COMMERCIAL BREAK)

… and as we remember those who sacrificed, we pay tribute to one service member, a marine missing in action for nearly 50 years, and his family's journey to bring him home.

(BEGIN VIDEOTAPE)

MICHAEL RYAN, SON OF WILLIAM RYAN: My dad, Billy Ryan, was an all-American Irish Catholic boy from North Jersey. My dad lived his life with purpose. He always wanted to do something that was meaningful. When the Marines were there saying he could learn to fly planes and be part of making a difference and serving his country, that resonated with him.

RADDATZ (voice-over): Michael Ryan didn't really know his dad, but has spent a lifetime learning about him. Michael was only 3 months old when his father, First Lieutenant Billy Ryan, just 24 years old, was sent to fight in Vietnam.

It was 1968. Ryan was a radar intercept operator flying in the backseat of F-4 Phantom fighter jets. He flew over 300 missions in nine months. Just days from his son's first birthday and planned R&R, Ryan had one more mission.

RYAN: They were actually bombing the Ho Chi Minh Trail and they were hit by anti-aircraft missile and their plane was shot down and the pilot was able to eject. My father was not.

RADDATZ: Lieutenant Ryan, among the 2,600 Americans missing in action.

RYAN: There was always that, you know, 1 percent chance that, did he live? Did someone not see his parachute? Was he a POW? As a young child, I mean, it was always a dream. I'd sleep and wake up to imagine if my father came home to me, you know.

That was something I always kind of held out hope for. And I think secretly my mom did too. So I wanted to do something more for him. I wanted to bring him home. And what we found out later, that the Marine Corps was doing that all along.

RADDATZ: In 1988, 20 years after Lieutenant Ryan disappeared, U.S. excavation teams were finally allowed wide access in Southeast Asia to search for the missing.

RYAN: I was learning that they were finding pieces and parts of the aircraft, I was finding that they may have found a strap from the parachute, however there wasn't anything substantial in terms of my dad's remains until recently.

RADDATZ: Military teams took seven trips overseas spanning several years. Finally, a positive ID.

RYAN: The first thing I did was call my mom. I mean, she was -- I mean, I've never heard her that excited and elated, tears of joy, you know, relieved, you know, I could feel that she had closure. And to me that was the best feeling.

RADDATZ: After a nearly 50-year journey, this month Mike Ryan finally bringing his dad home. First Lieutenant William Ryan, memorialized with full honors. But the moment bittersweet, an empty chair for Mike's mother, she knew her husband's remains had been found but passed away days before the service from cancer.

RYAN: I know in my heart, you know, she was there looking down because it was an amazing day and, you know, I just couldn't be more prouder of my father and his service to our country.

My dad is buried at Arlington National Cemetery. And that's a special place to be. That's reserved for heroes. And so this is going to be a special Memorial Day for myself as well as all my family and all the Ryans.

(END VIDEOTAPE)

RADDATZ: And we honor the Ryan family service this Memorial Day weekend.

That's all for us today. Thanks for sharing part of your Sunday with us. Check out "World News Tonight" and have a great day.