Um there is a big difference between Communism and liberalism.
Communism is a classless society of internationalism brought about by the dictatorship of the proletariat. Communism sees morality as bourgeois and prudish and rejects it for "polymorphous perversity." Communism rejects race and nation as bourgeois and advocates an international workers' solidarity.
Liberalism advocates a society built on freedom and individualism in both moral regards and economics. Liberalism rejects the government involving itself in economics and instead wants businessmen/private individuals to deal with their own economic affairs. Since liberalism supports freedom it rejects race and nation since they see both as social constructs that are about oppression and instead promotes an international economic system.
Okay I realise that both movements are left-wing and in many respects bring about the same ends and are only different in the means, but we must differentiate between the two definitions since liberals are NOT commies. However liberalism has a historical obsession of being "soft on Communism."