The counterargument to this is that dependence on the US military keeps other countries from putting in the resources to become military competitors. It's as similar argument to how sanctioning Chinese tech companies ends up encouraging them to develop indigenous technologies that will later compete for market share on other continents. The US having a dominant military presence globally ensures that other actors either don't even bother spending on a military or don't have conflicts they can practice their militaries on (a big problem for China when they can't see if their new toys actually work) If only the US has active military experience then it's a lot easier and cheaper to fight inexperienced competitors. Even for allies like Europe, if the US leaves the EU to develop a military and they get some experience with fully self-reliant overseas adventures in North Africa or the Middle East, how do you know they won't turn Fascist/Communist/fancy future political ideology one day (or the reverse for the US) and start launching invasions across the Atlantic?