All those billions have fed a lot of people around the world Curval, in many cases meaning the difference between life and death.
We (the US) have neither the resources nor the desire to be the world's government. When a country poses too great a threat to world security and/or freedom we step in, as we did in WWI, WWII, Communist expansion and a few other occasions.
If I misread your intent then I offer my apology.