Even the president does not act with complete power. There are geopolitical and other realities that constrain a president. Even if Ron Paul were elected, things would change far less than you might think.
It’s funny how often I hear that from Santorum supporters.. and ONLY from Santorum supporters. This must be the official answer to those who point out Santorum’s lack of a platform. “Well, he doesn’t need one, since not much will get accomplished anyway.” I’d rather have an active campaigner in office than the Pope.