America need to consider that Fujan and Guandong provinces are not isolated like kola peninsula or kamchakta. China can easily concentrate all of his airpower to sustain Taiwan annection, and in case of interference USA will surely lose some carrier groups leading fast to a larger escalation conflict where also mainland usa will be involved if the attack china mainland. Hint: nuclear war. The scope of china for taiwan (decapitate taiwan democratic party and stage a sort of hybrid war) is much easier than the soviet scope for western Europe (conquest of west germany and perhaps northern france). Consider Also that america is 12000 km away from taiwan and not only 6000 like from england