Larry Berman, an American historian, will return to Viet Nam next month to begin interviews and research for a new book on Vietnamese agent Nguyen Van Tau, alias Tu Cang. The former spy worked with legendary spy Pham Xuan An, who was the subject of Berman's first book which was critically acclaimed. Berman spoke to Culture Vulture about his new venture.

Why did Pham Xuan An choose you to write about him?

Pham Xuan An chose me to be his biographer because he read my book No Peace, No Honor: Nixon, Kissinger, and Betrayal in Viet Nam. He thought the book was straightforward, fair and balanced. So he trusts me.

I spoke with Pham Xuan An for two years before he agreed to allow me to write the book. But when he was sick and recognised that he had a very short time to live, he finally agreed to let me, an American historian, write about his life.

Fortunately, he lived another two and a half years. He gave me only two conditions: that he would not read my words until I finished and that I could not write down any details about certain matters until after he died.

However, I feel that An still kept many secrets. The secrets are relevant to several people and those who belonged to his network. At that time, I did not think that I could write a second book about him. But I updated the second edition to honour my promise to him.

You have met several American politicians and spies. Do you see any differences between Pham Xuan An and them?

I think Pham Xuan An is one of the best human intelligence agents, who completed his missions with a very simple network, without technology. For me, An is the best evidence for the use of human intelligence.

Initially, Pham Xuan An went to the US to study intelligence work from the Americans. But after the terrorist attack on 9/11 in the US, leaders of the CIA told Berman that they wanted to learn from An.

What was the attitude of Americans after they read your book?

There were many soldiers who had fought in Viet Nam during the war who were angry at Pham Xuan An for what he did. Many of the Vietnamese who live in California were angry also. They said I wrote about An's life from the Vietnamese point of view, calling him a talented person. They were upset that I called Pham Xuan An my friend. They said An should take responsibility for the death of Americans and Vietnamese in the South during the war.

The younger generation in the US, however, sees An as a person who brought peace, friendship and connection between American and Vietnamese. They admired An after reading about him.

What do you remember most about Pham Xuan An? Will you write more about him if you can gain access to other sources of secret information about him?

An was humorous and friendly; he was educated in the US. He was a great conversationalist and great talker. He was funny, and honest also. He spoke very candidly.

If I can gain access to other source information about An, I will write more about him. Possibly, 50 years later, a younger historian who can read Vietnamese well will write a new book about Pham Xuan An, telling the rest of the story. There are many files and reports in Viet Nam labelled top secret that no-one can access. They are kept in Viet Nam. I hope in the future that I will be able to have access to this information.

What was the most difficult aspect of writing about Pham Xuan An?

Trying to figure out who Pham Xuan An was. During the war, he had contact with several important politicians. But when the war ended, the real man was revealed and his friends did not get angry for what he did. — VNS