“Everywhere” meaning undefended airspace into which one masses a significant fraction of one type of strategic armament.
This was the savvy exploitation by Kyiv, once again, of Russian operational incompetence.
> there isn't anyone who will stop you from pre-positioning weapons adjacent to American strategic assets
You want to try driving a truck up to a USAF base? (EDIT: Where strategic arms, e.g. B-2s, live.)
This is a novel threat vector. It needs to be protected against with vigilance. That to requires active effort to counter doesn’t mean it’s OP. Just that defensive perimeters need to be expanded, units not needlessly amassed, air defences kept in check and those perimeters constantly (and completely) monitored.