You must understand that Presidents do not really make decisions based on what they believe. There are all sorts of folks around the President trying to convince him to act this way or that. At the beginning of his term, Obama had Keynesian economic advisors. Then they got thrown out, and free trade austerity neoliberals (many of them Jewish bankers) came in and took control. Obama’s policy was simply the policy of whoever had his ear at the time.
These Presidents don’t have as much agency as you think, and they are not dictators, though George Bush wanted to be one. At the beginning of his term, Obama’s advisors were called foreign policy realists, who, while still awful, a much better than the neocons. These people are actually halfway sane. That’s why they are called realists.