The game has been too global and interconnected for over 100 years. Natural borders are no longer impenetrable. There is no choice but to fight this battle far beyond our borders if we don’t want to eventually lose.
Every country taken over provides great resources and haven for the enemy. It’s not simply a prize. It is power. This is why we used to fight against even the smallest, most insignificant country falling into their control. Until we gave up on Vietnam. Then we started trading with commies for “peace” until we lost our entire means of production. 50 years later they are still enemies, they are far more economically powerful and we are weaker in every way that matters.
For example NK has become a nuclear proxy for China. Where humans are enslaved to threaten half the planet with nuclear fire to protect communist borders. While China further expands in the Pacific. Eventually they will be able to target any US city.
South Korea exists as their counter and has greatly diminished NK’s power only because of American blood spilled many years ago to hold the communist line.
Basically, an enemy colonizing the entire planet to do their will is eventually going to be powerful enough to do the same to us...
Your argument for this is more easily applied to Russians concerned about Americans pushing their way into far-off corners of the globe.