Just some thoughts and while I am not necessarily advocating it, I wonder what would happen and what the opinion of us throughout the world would be: IF we pulled every military person from all bases not in the country, cut all foreign aid to all countries unless there was a quid pro quo attached to it and greatly curtailed any material goods being donated to foreign sources. Though it will never happen, I'll bet the results would be interesting.
Here's my guess:
The first response would be to condemn our actions - loudly, often, and in unison. Then, we would be asked to pay restitution for are the hardship that follows.
And if we really did such a thing, the suffering would be monumental. Aggressive countries/leaders would bully and/or take over those territories/peoples that have relied on our protection instead of their own. Internal conflict in a variety of countries would quickly get out of hand. Economies would collapse further.
I envision outcomes like that of Zimbabwe when Robert Mugabe seized farms and began to redistribute land.
I imagine that any one of those three acts would have similar results alone and be completely catastrophic together.
I do think we could
slowly remove our military from most other countries. It would take negotiation, money, and time. I doubt we will ever be able to cut foreign aid - I foresee it mounting instead. Ditto material aid.