(CNN) Imagine the airport with no security. No metal detectors. No TSA guards. No luggage searches. Boarding an airliner with a firearm could be as easy as putting a pistol in your pocket and taking your seat.

That's the way it was in the United States in the early 1970s when an epidemic of airline "skyjackings" dominated the news. Hijackers' motives ranged from political to financial. Their destinations spanned North America, Europe and Asia and quite often included the island nation of Cuba. The hijackings took place against a backdrop of dramatic social change and the Vietnam War.

Three decades before the 9/11 attacks, these airline bandits triggered a chain of events leading to the modern airline security we enjoy -- and suffer -- today.

Author Brendan Koerner details the most fascinating of these dangerous high-altitude confrontations in his book, "The Skies Belong to Us."

CNN: How did the idea hit you?

Brendan Koerner: In October 2009 I was reading the Metro Section of the New York Times and there was a little item about this man named In October 2009 I was reading the Metro Section of the New York Times and there was a little item about this man named Louis Armando Pena Soltren who'd been a Puerto Rican nationalist, and he lived in the Bronx in the '60s. And he and two of his comrades in 1968 hijacked a plane from New York to Cuba.

He actually spent the next 41 years living in Havana. And then suddenly in 2009 he decided to come back to the US voluntarily. And so this piece was about the fact that he had been arrested the second he stepped off the plane at JFK.

I was always vaguely familiar with the fact that planes had once been hijacked to Cuba, but I really didn't know much about that era in aviation. It was a little bit before my time. So I started looking into this time period. And I was just blown away by how common hijacking was in America at that time.

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I was particularly intrigued by this one story. I was looking at names of people who had done this and it was pretty much all males, people with pretty obvious political motives. And there was this one name that leapt out at me. It was a young woman named Catherine Marie Kerkow, from a small town in Oregon, who had done this. And I really become interested in her case.

And that became something that took me down a four-year journey -- a four-year research and writing path.

CNN: How old are you? And do you remember hearing about any of these hijacking stories in the news when you were a child?

Koerner: I'm 37. The only hijacking story I really remember vividly from being a child was in the 1980s, there was a pretty famous TWA hijacking in the Middle East, I believe in Beirut. I was born after this hijacking epidemic, which pretty much ended in early 1973. So it definitely predates me.

CNN: If the Nixon administration hadn't clamped down and if 9/11 hadn't happened, do you think skyjackings would still be going on today?

Koerner: Ultimately the solution to it was a pretty prosaic one, in that after putting up with all these hijackings for so many years, they made a decision to finally compel all travelers to pass through metal detectors and have their carry-on luggage searched.

And pretty much immediately after instituting that regulation, skyjackings dwindled to almost zero. So it was a pretty simple fix, and one that had been resisted for a long time because they didn't want to inconvenience travelers. The airlines in particular were really terrified that their customers wouldn't fly anymore because they didn't want to be treated like criminal suspects just because they were flying. So they resisted very public calls for them to do this for many, many years.

Would this still be going on today? It's hard for me to fathom that we wouldn't have done something about this eventually. I think that they eventually put in those regulations when it became obvious that planes could be used as weapons of mass destruction.

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There's an incident in November '72 which I discuss in the book, when a Southern Airways flight was hijacked and the hijackers threatened to crash it into a nuclear reactor at Oak Ridge National Laboratory, unless they were given $10 million.

And that was really the straw that broke the camel's back. It became obvious that if that had happened there would have been a tremendous loss of life and destruction. So it wasn't just a matter of, "Well, let's give in to people and everyone will be safe." It became too risky at that point.

CNN: Your book describes the tipping point in the history of aviation travel where travelers have gone from being treated as welcome guests to -- for some -- feeling like they're being treated as potential criminals.

Koerner: That's exactly right. It's interesting that the fear of the airlines was that people would not fly anymore or they would lose a large percentage of their customer base. People would choose to drive instead of fly because they didn't want to put up with this intrusion.

But interestingly, when the dawn of the screening was covered in early 1973, pretty much universally people were in favor of it, because they recognized how dangerous the skyjacking epidemic had become.

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I talk in the book a little bit about these reporters swarming these airports on the day they launched universal screening and hoping they would catch some kind of conflict or disgruntled fliers. But pretty much to a man and to a woman, people welcomed the new security because they recognized -- especially in light of what had happened in 1972 with all the craziness -- that this was a necessary step.

CNN: Can you share some personal details about your research process and maybe some unique experiences or surprises you ran into along the way?

Koerner: One thing that's interesting for me is, I travel a lot as a journalist, but I've never really paid much attention to airline personnel on the planes and the lives of pilots and flight attendants. And that really became something I became very deeply immersed in.

With this project I was trying to track down flight attendants and pilots who had been on this hijacked flight which is the focus of the book -- Western Airlines Flight 701.

I traveled all over the country talking to people who'd been on the flight to get their recollections of it. Most interestingly, I actually tracked down one of the hijackers. He was living in San Diego. And I found him and it took me a while -- he was difficult to find. I couldn't get a phone number. I eventually just got an address for him through a series of happy accidents.

I sent him a letter and a copy of my first book and he was kind enough to respond. And that was a tremendous experience and a tremendous boost for the book, to get his recollections and memories and details that only he had.

CNN: Was that Roger Holder?

Koerner: Yes, it is.

CNN: Based on what you knew about the hijacking and based on the man you met -- how do you think he has changed?

Koerner: You have to keep in mind that he did this act when he was quite young. He was 22 years old when he hijacked this plane, and he'd served four tours in Vietnam. I think the combination of youth and the difficulties associated with his military service and maybe some other factors -- maybe some psychological factors -- made him an angry person.

And he lashed out. He acted out in a pretty extreme, spectacular kind of way with this hijacking.

I think age and experience changes everybody. And the man I met was a very thoughtful, very calm, incredibly charismatic person. It was really a joy to sit down with him. At the same time I could see him struggling to come to terms with what he'd done and what his role in history was.

For him, he had pretty fond memories of a lot of aspects of this. Not so much causing people terror or consternation -- but the experience that came afterwards with his travels and being in the public spotlight was something that weighed heavily on him and he thought about quite a bit.

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CNN: So why don't we know what happened to his co-hijacker Cathy Kerkow?

Koerner: That's the million dollar question in the book. I don't want to give too much away, but certainly the last time that she connected with Roger, she said she was going to Switzerland for a brief trip with friends.

Based on information I have, I believe she tried to carve out a new identity -- that she decided that this was her chance to gain a new life. They were waiting around to be put on trial in France for hijacking and she didn't know how that was going to turn out.

Her relationship with Roger had come to an end -- at least romantically. And I felt that she sensed that this was her opportunity to move beyond all this -- to move beyond the folly of her youth.

CNN: When you were writing the book were you sensitive to glorifying the anti-hero aspect of Holder's and Krekow's story? I've seen them compared to the notorious 1930s bank robbers Bonnie and Clyde.

Koerner: I think you need to approach these kinds of stories with empathy for everyone involved. At the same time you do have to be judgmental to some extent and recognize that their actions caused a lot of people a lot of pain.

And I know for a fact that they're aware of that.

It's a deeply human story, and all humans have their pluses and minuses, so I think that should come through in all the characters in this book.

CNN: You write about Holder's anger about prosecutors' treatment of political activist Angela Davis. During your research did you reach out to Davis?

Koerner: I didn't, because from what I understand she doesn't like talking about the past, and she never met any of these characters. I did reach out to some other people who wouldn't go on the record with me, for example (Black Panther Party leader Eldridge Cleaver's widow) Kathleen Cleaver, who I know was an eyewitness to these events.

CNN: Could you describe Fidel Castro's Hijacker House? And how and why did Cuba set itself apart during all of this?

Koerner: A lot of people were hijacking planes to Cuba in the '60s. A lot of hijackers, I think, thought they would be greeted as heroes when they arrived in Havana. But it was actually quite the opposite.

Fidel Castro had no patience for these crazy Americans coming with planes with their various motives. So as an American you basically faced one of two fates when you went to Havana with a stolen plane.

One, you would be put in a South Havana dormitory called Hijacker House, where you were given about 16 square feet of living space with a cot, and they give you 40 pesos a month, (and) you kind of have to fend for yourself. It was a really awful life.

And if the government really didn't like you -- for example, if you were violent on board the plane or if you robbed any of the passengers -- they would actually send you to these gulags in the south of the country where you would harvest sugar cane. And the conditions there were just absolutely nightmarish.

There was a hijacker named Anthony Bryant who wrote a memoir after spending about 11 and a half years in prison in Cuba for taking a plane. The details he has in that book are just really shocking about the treatment of prisoners there.

CNN: If I traveled to Cuba today, would I see any remnants of that time when Cuba was a hijacker destination?

Koerner: Well, you certainly would, because there are still some hijackers living there. Most came back, but there actually are still a few who decided stay there. Some of them make their living as tour guides, or translators or fixers for journalists. There are still people there who went there in the '60s or '70s and never came back.

CNN: Who was Capt. Eugene Vaughn?

Koerner: Eugene Vaughn was a Pan Am 747 captain, and he was running a route from San Francisco to Saigon with stops in Honolulu and Manila and Guam, I believe.

On the way to Southeast Asia, one of Vaughn's passengers was a South Vietnamese native who had just graduated from the University of Washington and was on the way home. He decided to hijack the plane and take it to Hanoi to protest the bombing of North Vietnam.

They land in Saigon and the captain went back and basically tackled this hijacker.

Another of the passengers was an ex-cop from San Francisco. Vaughn knew the ex-cop was armed and Vaughn had him shoot the hijacker to death. The captain then literally picked up this hijacker and took his body to the rear exit of the plane and threw the corpse onto the tarmac. He said he did it because he was so offended that this guy, who would challenge his command, would remain on his plane -- even while dead. He just had to get him off the plane.

When he returned back to the US, a lot of people hailed Vaughn as a hero, because this was a moment in America during the skyjacking epidemic when the public was really through with it. They were really finished. It was no longer quaint or funny when people were hijacked. There were actually deaths involved and there was a lot of terror going on.

That was kind of a turning point in the epidemic when it became clear the public wouldn't put up with this anymore.

CNN: What takeaways can you offer modern-day travelers based on what you've learned while writing this book?

Koerner: When you're going through security -- and we all have our complaints about what the TSA is doing, and certainly a lot of those complaints are valid -- but I think we need perspective about what life was like when we had no security, or very poor security.

There are reasons why things are the way they are. And we can certainly have debates about the efficacy of certain techniques and tactics. But I think we also have this other perspective. There was a time when there was no security and we had this awful, awful crisis. And I think it would be even worse today if we stripped away a lot of security.