[rcocean]

I wonder if Einstein would have written the letter on Sept 2 1939? The nazis and the communists were allies then and Einstein probably followed the partyline.

[snarks_when_bored]

I think your estimate of Einstein's political sympathies is mistaken. Einstein was first and foremost a humanist. He was not a rabid anything, especially not a rabid political theorist.

He was forced to leave Europe in 1933, and, after arriving in Princeton, never left there. He became an American citizen in 1940.

He was a gentle man who sought peace and well-being for all, but who also could see clearly enough the nature of the threat posed to the world by Hitler and the Nazis. That is why he agreed to sign the letter posted above by IonImplantGuru.