Why did Communist membership increase in 1930s?

Answer 1

The same reason Fascist groups increased in membership in the 1930's, the Great Depression. Some saw the free market as a failed system, and reached out for a type of economic for a "new" beginning. the largest rise was in Fascist ideology, Germany, Italy, Japan, and Spain, all chose dictatorial, expansionist leaders, believing only the theft and enslavement of "weaker, inferior" countries could improve living conditions in their own.

Communist Josef Stalin joined Hitler of Germany for a time, before Germany invaded the USSR; at that point, Stalin joined the Allied forces, America, Britain, Free France.

Though there was an actual threat to the US from fascist sympathizers, Communism during the Great Depression did not increase beyond a few 'roundtables' of intellectuals, far removed from power. Never a threat, the nation united against the Japanese fascist attack on Pearl harbor, in 1941, when Hitler declared war on the US.