One balmy day last summer, I found a folder with the emblem of the Israeli secret service in my mailbox. It was a formal-looking, government-business envelope, the sort one might expect to receive from the I.R.S. or Social Security. For me, however, it was the pinnacle of a journey of historical inquiry that had lasted almost four years.
Since beginning work on my new book, Fugitives: A History of Nazi Mercenaries During the Cold War, I had labored to gain access to intelligence-service archives, the only source where one might find reliable answers regarding the activities of former Nazi spies who evaded post–World War II punishment, roaming Cold War Europe and the Middle East in the 1950s and 1960s.
