For countries where we have lost billions to "help" them, do you believe those countries should pay us back? If so, how?

The US does NOT "help" out of a sense of altruism; the US seeks to further its own political and foreign policy objectives, and that is the sole reason we are forward based in locations around the world in places like Japan, South Korea and Germany, and the reasons behind our military interventions. They are most often presented to the public as gracious and altruistic actions that are intended to "liberate" the subjects of oppressive totalitarian regimes, and in some cases, that is a second order effect, but it is NEVER the primary reason behind the use of military force.

There are a few exceptions, like Somalia and Rwanda.

The US, like every other sovereign nation, and like very other super power in world history, attempts to further its own best interests when it opts to use military force.

So if we're attempting to further our own best interests, do you still think it reasonable to ask other nations to "pay us back" for that?

So who exactly asked us to spend billions to overthrow Saddam in Iraq? Yeah, nobody.

When we "help" a country we do it with our own national interests in mind. We don't help any nation out of the pure goodness of our hearts.