Why surviving supplies can still be unusable

Could Iranian strikes have destroyed American prepositioned supplies during the recent conflict?

Most stores were protected in hardened sites, but their location could still trap them far from the fleet that needed them.

The supplies themselves were unlikely to be destroyed because much of the stock was held in hardened facilities. The harder problem was moving it from established depots to ships operating at greater distance. Fleet stores arrive by sea, fill large warehouses, and usually leave through the same port system. Without a strong rail network or alternate ports, cargo can survive an attack and remain stuck in place. Standoff weapons also remove any reason for a navy to close the range merely to give its opponent a fairer fight.