I don’t see that US leaving NATO would actually harm their hegemony. It might even strengthen it because US will no longer have direct obligations to Europe, that means Europe will be forced to beg US for help in case of a crisis as opposed to take it for granted.
They’d sooner axe an isolationist president, than do anything that’d harm their global hegemony, like dismantling NATO.
I don’t see that US leaving NATO would actually harm their hegemony. It might even strengthen it because US will no longer have direct obligations to Europe, that means Europe will be forced to beg US for help in case of a crisis as opposed to take it for granted.
The US wouldn’t really have the veto capabilities on NATO decisions like they currently do.