if there’s one superpower close to reaching the power level of everyone else combined, then everyone-else will ally to bring them down, maintaining a multipolar balance of power.
I hope they don’t use nukes when they do that because that way, everyone loses.
I would define “physical” as the set of rigid rules governing reality that exist beyond our experience and that we cannot choose to change.
I can cause water to freeze to form ice using my agency, but I cannot change the fundamental rules governing water, such as its freezing point. These rules go beyond my agency and, in fact, constrain my agency.
Physics constrains everything else in a way that everything else does not constrain physics, and thus the primacy of physics.