FDRs government was overflowing with Communist sympathizers who were pushing for war with Germany.
Today, like then, there are bad actors littering our government actively working against our interests to settle a score half a world away.
You have it backwards. The communists were calling FDR an imperialist and were totally against war with Germany. They were doing this on direct orders from Stalin.
Lillian Hellman was blacklisted and threatened by the communists for writing Watch on the Rhine, because it was anti-German, even though she was in good standing before that.
And Hellman was so loyal to communism before she trashed Finland, and got into a feud with Tallulah Bankhead about it for decades.