To make the planet, the world, a better place for Americans.
Your apparent lack of tolerance for things that do not directly serve your self interest is short sighted and foolhardy. It's sad that your way of thinking has carried the day in the US.
Some of the spending probably does fit that description, but I bet if we had a truth oracle that could actually tell us, it would be a lot less than you think.
You're going to feel really weird when, in response to the US's waning engagement with global geopolitics, a bunch of countries form trade organizations and jettison their dollar holdings. Kinda like how a bunch of dairy and grain farmers felt when they realized the "welfare" programs they loved to bitch about were actually poorly camouflaged agricultural subsidies. Whoops.
We live in a polity. That polity can be generous, well-regarded, respected, feared, and despised. The admixture of those attitudes affects our polity’s ability to pursue its interests.
(I also happen to think that our polity should assist the least fortunate on its own merits, but you may not)
Cool, I want $0 of my tax dollars going to fuck over Latin America when the people of a country there elect anybody slightly to the left of Genghis Khan.
I want $0 of my tax dollars going to bombs to Israel
I want $0 of my tax dollars spent on military bases abroad.
Let's curtail the big stuff and then we can pinch the pennies, or at least let's compromise and do both.