How did ww1 contribute to the russian revolution?

Why did roosevelt support a europe first strategy even though it had been japan that had first attacked the us

Germany italy and japan formed the tripartite pact in part because they: a. hoped to convince the united states to stay out of world war ii b. share the ruling philosophies based on communist economics c. resented the agreements they were forced to sign at the munich conference d. believed their territories were threatened by aggressive foreign states

Did the both the us and ussr have atomic weapons after 1949