I'm offering a rationale, not a defence. Not everything the USA has done has been selfless and not everything has worked out for the best, maybe not even the m

I'm offering a rationale, not a defence. Not everything the USA has done has been selfless and not everything has worked out for the best, maybe not even the majority! But I must challenge the original assertion: when you take into account both capacity and intent, America was by far the most beneficient power of the 20th Century.