The unprecetended plan, branded FORTRESS by Pentagon planners, aims to make major military bases across the continental United States capable of functioning independently for at least 90 days, according to documents obtained by the news outlet.

"We don't want to rely on standard civilian municipal infrastructure to run our national defense. We just simply can't. It's an intolerable risk," DoD spokesperson Sean Parnell said.

The Pentagon is exploring portable nuclear reactors, massive battery installations, and independent microgrids that would allow bases to disconnect from civilian power systems during prolonged blackouts. Officials have long feared that the lose of electricity could cripple communications, logistics, weapons production, and military command structures.