[Spirochete]

He had access to decrypted Soviet message traffic, now known as the Venona Intercepts. He knew exactly who the commies were because they were named in these messages.

This is how the Rosenbergs were exposed. The fact that the Soviet code had been cracked was a closely guarded national security treasure, and so the moles were not outed with unerring accruacy, lest the Soviets suspect.

McCarthy was right about communist subversives, but *why* he was right could not be disclosed at the time.

[txhurl]

Thanks for the info!

[sphinx]

The fact that the Soviet code had been cracked was a closely guarded national security treasure, and so the moles were not outed with unerring accruacy, lest the Soviets suspect.

The irony is that the Soviets knew about the Venona intercepts almost immediately, because both the U.S. and British governments had been penetrated at very high levels.

I have never read much about J. Edgar Hoover, but I wonder how much of his behavior may have been driven by the realization that his own government had been compromised and that he couldn't trust the chain of command.

[edwinland]

I hadn’t heard that he had access to the Venona transcripts. Do you have a source for that?

[Sherman Logan]

Sorry, but it’s very unlikely indeed McCarthy had direct access to intelligence from Venona, though I suppose it’s possible somebody was leaking him results.

Truman himself didn’t have access to Venona, so it seems unlikely an at the time obscure senator from WI would.

Also, Venona was almost entirely from 42 to 45, with a very few as late as 48.

McCarthy was more or less right when he talked about the number and penetration of Soviet agents. It is very unlikely he had any clue who they were.