Obama promised everybody everything to get elected. No one could possibly deliver on what he promised, but people around the globe totally bought it. He is one man, and the president isn't even all that powerful in the US political system. Congress controls the purse strings, and so it will be run by his opposing party. Then nothing will be accomplished, and they will all be able to blame each other as usual for not fulfilling their election promises.

I think religion matters in the US to the extent that it would be very hard for an atheist to get elected to any office. Americans expect their politicians to have a little humility by believing in a higher power other than themselves.