(NewsNation) — Osama bin Laden, the terrorist and mastermind behind the September 11, 2001, terror attacks, was killed May 1, 2011, by U.S. Navy SEALs at his compound in Pakistan.

Many Americans don’t know that the SEALs also found 500,000 secret files including audio recordings and personal letters from bin Laden in the compound that same night.

In 2017, the CIA declassified most of the letters without context or translation.

Since then, Islamic scholar Nelly Lahoud, who’s a leading expert on al-Qaida, has been translating and analyzing all of those documents. Lahoud was interviewed Monday by NewsNation’s Brian Entin, who was substituting for host Ashleigh Banfield.

Lahoud published her findings in her new book, “The Bin Laden Papers: How the Abbottabad Raid Revealed the Truth about al-Qaeda, Its Leader and His Family.“

Below is a full transcript of NewsNation’s interview with Lahoud, edited for grammar and clarity:

Entin: Were you surprised when you first learned that there were so many files that backed up everything?

Lahoud: It’s astonishing that these files actually exist because the security protocols with al-Qaeda was that bin Laden should have destroyed these files. About a month before the raid, one of bin Laden’s top associates reminded him, in one of the letters, that he had destroyed all his files himself, and reminded him (bin Laden) that he should do the same.

Entin: I would imagine, it’s almost like you had to piece the story together, right? It’s not like it was all laid out in a perfect order.

Lahoud: That’s actually correct. To be clear, out of all these files, I determined that the text files, about 97,000 of them are actually the most important.

And with the help of two research assistants, we went through them systematically. We identified what was the internal communications, which is really what was important. And we identified about 6,000 Arabic pages that really formed the basis of the book.

Entin: I think what I found very disturbing, in what you discovered from the files, is that bin Laden actually had a plan for another 9/11, and there were plans involving private planes, attack trains, and bomb oil tankers. What else was he planning?

Lahoud: The fortunate part is that in the aftermath of the Taliban collapse, in 2001, al-Qaeda was shattered. It didn’t really recover its operational capabilities. And this is actually something that we really didn’t know before.

We learned that in 2004, he was planning some operations, firstly, to derail trains in the United States. At the time, he had just reconnected with his associates, and it was pretty much a non-starter because they told him of his afflictions, and so on.

We can see through the letters that bin Laden was continuously itching for more international terrorism, and he wasn’t able, and his group wasn’t able, to deliver.

By 2010, we find him writing to his associates, that unless we really change our strategy, and unless we deliver what he called a balance of terror with the United States, al-Qaeda … as an organization is going to come to an end and is going to die.”

So he spent that year meticulously planning attacks that the effective which would far exceed 9/11. And his plan was to destroy about 30% of the American economy. And he wanted to do that by sinking the largest oil tankers, and he had done his homework. There are about 730 of these oil tankers around the world. There’s a limited number. Each one of them carries about 2.2 million liters of crude oil, and so he thought that by sinking a large number of these oil tankers, he would be able to crush, or at least destroy 30% of the American economy. His main target really is to adversely affect the income of every American citizen.

Entin: It’s terrifying to think about those plans. Would he just sort of come up with the conceptual ideas, or was he actually planning?

Lahoud: He was very methodical. He thought of details large and small. It is quite disturbing to find how, how attentive to detail, and how ambitious he was in this.

Entin: Bin Laden had this very interesting relationship with his wife and daughters, where they did more than I think a lot of people realized, right?

Lahoud: Absolutely. In fact, the letters paint a vivid portrait of the life and the Abbottabad compound. We discover that many of the public statements that we’ve heard bin Laden deliver over the years are actually effectively co-authored by his daughters, Miriam and Sumaiya. His third wife, Siham, also contributed to the editing.

What was also surprising is that nine out of the 16 people who lived in the bin Laden household were actually children, and we get a sense of the life of these children. They were home schooled in the compound. It seems that the bin Laden family tried to afford these children a normal life, in a very abnormal setting. They were not allowed, for instance, to play outdoors unsupervised by an adult, just so that they wouldn’t get the attention of the local authorities to think that might be people in this compound speaking a different language.

Entin: So fascinating to find out what was going on inside that compound that we all heard so much about. And scary to think of what may have happened if some of those plans actually went through. Nellie, thank you so much for being with us tonight.