seems like you don't understand politics and economy at all...ah it can't be helped
remember the marshall plan after WWII ? mexico? etc...same is happening in haiti right now...opening one of the last possible export markets in the world for the US.
don't get me wrong, i don't think that you americans are stupid or something, but it has been the politic of the US since WWII.
edit: erm yeah for those too lazy to search http://en.wikipedia.org/wiki/Dollar_Diplomacy