[sofixa]

The Communists didn't fight major battles against the Japanese, they didn't have the resources for that after the Nationalist purges and civil war. But neither did the French resistance against Nazi Germany, does that mean they didn't resist at all?

The Communists used guerilla tactics, to much success in some cases. Who did more to stifle the Japanese war effort is an impossible question to answer, but both sides of the Chinese Civil war contributed in the fight, each to their own strengths.