Here is a description from 1998, there have been a lot of changes since then, most of these mention the Army but all the services maintain these storage centers where they need them.
“The Army prepositions three sets in Europe. The other four
sets are prepositioned in Kuwait, Korea, Qatar, and aboard a fleet of ships.
Other Army prepositioning efforts include operational projects and sustainment stocks stored ashore worldwide and on ships.
So correct!
These stockpiles of vehicles and munitions are our response to the reality that, unlike in WW I or WW II, the bad guys just won’t hang around for us to get our act together and ship enough munitions over to whup ‘em.
It took, ten to twelve weeks to gear up for Desert Storm? Modern warfare take lots of weapons and systems, and lots of weapons systems means shipping across the Atlantic or the Pacific. And shipping takes time and coordination.
Do our lefties think that Iran, Russia or China will just hang around making speeches for a few months until we finally get the logistics in place to blow them up?
Nope, making speeches is the job of our current Pentagon and Congress.