Capitalism, or at least the version that is expressed by the United States, post WWII, represents the best chance for the MOST people by FAR, as opposed to any system the modern world has ever seen. And if it were not for that prosperity, the world would be a much more inhospitable place.
It is a practical impossibility to quantify the amount of suffering that the United States has alleviated, world wide, since they decided to enter in to WWII.
It's not perfect. Nothing is. But I'll never understand it, when US citizens rail against it, and characterize it as evil incarnate. I just have to keep in mind that all of that comes from ignorance. They just don't KNOW how much the United States has, on balance done for the rest of the world. And also, what it would BE right now, if not FOR the US.