next president will be a lot weaker than Bush, for better or worse.

Bush has been the strongest US president in at least 50+ years. He got most of what he wanted out of congress, not having to use any veto his first six years (a historical record not even Washington or Roosevelt could match!)

The Republican base is still solid and loyal (and to the right of W.), so if a Republican wins, he will have to follow basically the same policies.

If a Democrat wins, she/he will find a majority coalition of Republicans and Conservative "blue dog" Democrats in Congress blocking any of her far leftwing ideas.

Since the Vietnam war, the Democrat Party had been deeply divided especially in foreign policy, this is the reason why Carter and Clinton had been so weak or "centrist" (i.e. not main stream leftist democrat) in foreign policy.