I asked you for a detailed scenario on how this would be a significant existential threat to the US for scrutinizing. Of course you couldn't deliver.
Israel's survival is the business of Israelis. Mongolia's is the Mongolians. America's health (my country) is the business of Americans.
We can no longer (if we ever could) afford to sacrifice for the sake of others. In fact, it harms us.
While on the surface your position may look attractive, the long term repercussions would be disastrous. You, and many others on this thread, are calling for the 100% cutting of all foreign aid to any country that receives aid. Can think of how doing this might result in counties such as Russia, China, Iran, N. Korea, and others gaining influence around the world which would be in direct contravention to our national security interests?
Can you consider how our economy might actually be negatively impacted through the course of action you're demanding? Or, perhaps you believe that the U.S. can also, at the same time, completely drop out of the global economy and become completely self-sustaining just within our own borders. That fence on our southern border that people have been asking for would need to also be built on our northern border, and we would need to build barriers on both coasts. Is this what you're suggesting we should do?
Consider that there are natural resources which our country needs, which can be found overseas, but we've ended our dealings with all of the other nations of the world. Where do we turn to obtain resources we don't have or produce ourselves? Perhaps the moon? Mars? Jupiter? The world is a complicated place, and requires grownups to manage it. Not those who would say, “I'm angry at you so I'm going to take my toys and go home”.