I see your problem you think the president of the USA is actually a useful position. The president of the USA is actually the least powerful, least effective job in the USA.
The president doesn't make laws congress does, the president doesn't decide which laws are fair or balanced the judicial system does. The president doesn't even decide details of policy only vague generalities.
The president( i don't care which ones you like they all fall into this) can't make decisions. he can only choose between choices others make for him. he has three basic tools Force(military or civilian), Legal(lawyers), or Diplomatic(Negotations, etc) However he can't use force for anything but quick attacks or else congress must intervene. He can use legal but lawyers aren't useful for much. Diplomatic only works when the other party actually is willing to change.(that's why you can't negotiate with palenstine/isreal or the tea party, neither side can look at things from anyone else's view)
There is a reason why Presidents go into office looking healthy and come out Physically healthy but looking like they went through a meet grinder. Because they get all the blame, very little of the credit, and can actually change very little.
The president controls the price of oil about as much I do. The president controls the budget of the country about as much I do.
If your curious look up what the president is actually allowed to do in most cases all he can do is advise someone else to look into the problem and report back. Take the IRS scandal. I would be willing to bet the president knew about it a while ago. however he couldn't actually change the policies or punish people because congress ultimately controls those positions.
This true of every president they can at best suggest. whether or not they get listened to is another story.