America is a bit slow but is the force of the Allies. I usually abandon Asia and just move the fighter and infantry to India if Japan does not kill them. Then i buy 1 bomber per turn move to UK and industrial bomb Germany every turn while building up my navy at USA. Once my navy is large enough to withstand German aircraft i move to UK and have a fleet of transports at UK and USA and rotate every turn to attack western Europe every turn. If Japan does not Pearl Harbor i normally move the Navy to UK to get Germany on a 2 front war ASAP.
If Japan does not “Pearl Harbor” Sometimes i buy subs first turn consolidate my USA navy then attack Japans waters and force them to buy industrial complexes and buying time to buildup India with UK and possibly place US industrial complexes in Asia. This can really put japan back a turn or two. it really hurts Japan if they are buying transports if they see it coming they are force to defend by buying navy or buy industrial complexes which takes pressure off of Russia and India.