Sen. Richard Blumenthal (D., Conn.) appeared in three cable news interviews on Monday after President Donald Trump attacked him for "lying" about his service in the Vietnam War, but none of the interviewers pressed Blumenthal about misrepresenting his military record.

"We have learned something important since the days that I served in Vietnam," Blumenthal said in 2008. "And you exemplify it. Whatever we think about the war, whatever we call it — Afghanistan or Iraq — we owe our military men and women unconditional support."

But the Connecticut Democrat never served in Vietnam and took repeated steps to avoid going to war, including at least five military deferments.

The New York Times documented Blumenthal repeatedly misleading the public about serving in Vietnam and reported, "It does not appear that Mr. Blumenthal ever sought to correct those mistakes."

Blumenthal admitted in 2010 that he had "misspoken" about his service. "I regret that, and I take full responsibility," he said at the time.

Trump on Monday castigating Blumenthal multiple times on Twitter for lying about his service after seeing the senator on CNN's "New Day."

"Never in U.S. history has anyone lied or defrauded voters like Senator Richard Blumenthal," Trump tweeted. "He told stories about his Vietnam battles and conquests, how brave he was, and it was all a lie."

"He cried like a baby and begged for forgiveness like a child," he continued. "Now he judges collusion?"

Never in U.S.history has anyone lied or defrauded voters like Senator Richard Blumenthal. He told stories about his Vietnam battles and…. — Donald J. Trump (@realDonaldTrump) August 7, 2017

…conquests, how brave he was, and it was all a lie. He cried like a baby and begged for forgiveness like a child. Now he judges collusion? — Donald J. Trump (@realDonaldTrump) August 7, 2017

Trump also tweeted later on Monday that Blumenthal "should take a nice long vacation in Vietnam, where he lied about his service, so he can at least say he was there."

I think Senator Blumenthal should take a nice long vacation in Vietnam, where he lied about his service, so he can at least say he was there — Donald J. Trump (@realDonaldTrump) August 7, 2017

The attacks on Blumenthal put a spotlight on the senator. He had the chance to respond during three separate cable news interviews, which focused on Trump's attacks. Blumenthal was interviewed separately by CNN's Don Lemon and Wolf Blitzer, and by MSNBC's Chris Hayes.

None of their questions focused on the veracity of Trump's attacks, and none of the interviewers pressed Blumenthal on misleading the public about his military service.

At one point Blitzer noted that Blumenthal never actually served in Vietnam, but he did not press the senator on the issue; the question was phrased as an opportunity for Blumenthal to respond to the president directly.

Don Lemon's Questions ("CNN Tonight With Don Lemon")

"Senator, four tweets that are incredibly personal, very strong language. I'm sure you had a reaction to it, it's, it's awful."

"I think people understand what you're saying, and I know that you want to take the high road on this, but I mean that is a personal attack on you. And I understand you're right it's a very serious investigation, but those words have to hurt when the sitting president of the United States targets you. You have to feel that."

"Why do you think he bullies, he has bullied other people and some he'll hold his powder for he won't do it. Why do you think, you said it's bullying in your own terms. Why do you think he bullies you so much? And why do you consider this bullying?"

"My ultimate question: do you think that the public sees through these attacks because President Trump inflated how many people attended his inauguration. I'm sure you remember that. He lied about phone calls with the Boy Scouts, the president of Mexico, talks about things being the biggest or the best, he's exaggerator in chief. And this is our new CNN poll, only 24 percent of people say they can trust what's coming out of this White House. Do you think the public sees through these attacks?"

"Well, that's the problem, I think, I think people—I think the president realizes as you said it's broadening in scope. He wants to limit the power of the special prosecutor. And you know Deputy Attorney General Rod Rosenstein can investigate any evidence of any crime he uncovers. Do you think the president's threatened by that?"

Chris Hayes' Questions ("All In With Chris Hayes")

"Joining me now is Senator Richard Blumenthal, a Democrat from Connecticut, member of the Senate Judiciary Committee. Your response to the president's tweets?"

"I understand that and I understand why you're saying that. And it's a substantive matter and I understand why you would hold to that. As a human being, what is your reaction when the president of the United States goes on a rant about you?"

"Do tweets like today change your assessment of the president's fitness for office?"

"What makes you say, you say there is a collision course here. Obviously there were signs the president was interested in getting rid of Jeff Sessions. And he launched a similar kind of barrage of tweets against Jeff Sessions in a kind of aggressively passive aggressive fashion for about a week. He seems to have laid off there. Do you think the coast is clear?"

"I admire your discipline here. And I'm gonna, you're gonna try to ask this one more way. Because I think a lot of people wake up to tweets from the president of the United States. And even if they've made an assessment of his character still find it shocking, frankly. So I guess do you understand why people see something like that this volley of extremely mean-spirited aggressive and almost obsessive tweets. Do you understand why people ask the question, ‘What is wrong with this individual,' when they see tweets like that?"

Wolf Blitzer's Questions ("The Situation Room With Wolf Blitzer)