While Bohm was in exile in Brazil he had his US passport confiscated and felt that he was being watched and followed. Following his death I therefore applied to the CIA for a report under the US Freedom of Information act. (The FBI would not have been involved in monitoring a US citizen outside his country.)
The answer I received from the CIA was rather amusing. Firstly, they would not admit that such a document existed. But if it did, they wrote, then it would not be released on the grounds of national security.
In fact, Bohm’s preoccupation in Brazil was not with American politics but which former Nazi sympathizers who were arriving from Germany to take positions in the university. In particular there was talk of creating an Institute of Theoretical Physics at Sao Paolo with Heisenberg as co-director. Bohm’s concern was they would let “the rest of the Nazi Vermin in,” and wrote to Einstein about his concerns.