Foreign aid isn't really a very big part of our budget. It's much smaller than most people think it is.
What's stupid and unnecessary? Things like building that idiotic embassy in Baghdad. The largest and most expensive embassy we have. What on earth was the point? And now we're doing something similar, though not quite as pricey, in Afghanistan.
And what about military spending so unnecessary even the military doesn't want it? I'm referencing the refurbishing of old tanks. The army has said unequivocally that it does not want the tanks, refurbished or not. But it's some politician's pork project, and so… It is, of course, creating jobs, at least for a short time.
The Donald, however, is "very militaristic". He wants to increase military spending, and, he says, decrease taxes. That is a recipe for disaster. It seems also to have escaped his notice that we aren't fighting conventional wars anymore.
Actually, Clinton was paid $600,000 to give several speeches to Goldman Sachs, which, last I heard, isn't a non-profit. But I agree with your general point: do colleges and universities really need to hand out big speaking fees? A certain amount of "prestige" stuff will bring in alumni donations, but there's no reason to go overboard. Many prominent people will be thrilled if you just give 'em an honorary Ph.D.
As for Social Security… That won't be going anywhere.