As a historian, I rely on facts to understand and analyze the bigger story.

I look at the evidence, hear the arguments, and make a determination.

We rely on our government to do the same.

We rely on the government to tell the truth, to give us the real story.

But we've learned over the past few decades

that government officials sometimes hide important facts from American citizens.

When I was a graduate student, I was writing a book about the investigations

of the intelligence community after Watergate,

which meant that I needed to interview a number of senators, journalists,

and spies who were still alive.

Most of them were surprisingly willing to talk to me,

even two former heads of the CIA.

To each interview, I brought a list of questions in a tape recorder.

I would begin each interview by asking if I could record the conversations,

and they all agreed.

I learned quickly that the best conversations often happen near the end

when I turned off the tape recorder.

The person I was interviewing would say something like,

now that that thing is off, let me tell you something.

And sometimes, they would tell me a conspiracy theory.

These had been some of the most powerful men in the country.

Off the record, some told me they believed that the CIA had secretly sabotaged

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