The Pentagon is developing a requirement that major military bases in the continental United States sustain essential operations for at least 90 days without outside support. The initiative, called FORTRESS, extends beyond keeping the lights on. Bases would need independent supplies of water, fuel, and communications, alongside reserves of ammunition, medical supplies, electronics, and spare parts. Proposed power sources include portable nuclear reactors, batteries, and microgrids capable of disconnecting from civilian networks.

Defense Secretary Pete Hegseth introduced FORTRESS in late September. Officials are assessing the needs of roughly 500 installations, but the Pentagon has released neither a cost estimate nor a completion deadline. Fully meeting the goal is likely to take decades. Separately, Britain launched a campaign urging households to maintain three days of emergency supplies, including drinking water, food, cash, and backup communications.

Neither government has announced that war is imminent, and the efforts are not known to be coordinated. Yet both reflect growing concern that cyberattacks, sabotage, or conflict could interrupt the infrastructure on which military operations and civilian life depend.

Military power largely depends on civilian systems built for commerce, not combat. A base can possess advanced weapons and trained troops yet struggle to function if its electricity or water fail. Attacking those dependencies offers an adversary a way to weaken American forces without confronting them directly.

That concern has an established basis. In 2024, American intelligence and cybersecurity agencies warned that Chinese hackers had penetrated communications, energy, transportation, and water networks, potentially positioning themselves to disrupt essential services during a conflict. FORTRESS was subsequently created to address the military consequences of that vulnerability. Still, there is a substantial economic challenge, as maintaining spare capacity and adequate stockpiles, as well as alternative suppliers, costs more money precisely because so much of it is likely to sit unused.

Commercial efficiency tends to reward lean inventories and concentrated production; military preparedness requires paying for options that remain available when the cheapest supplier disappears.

Washington will also be tasked with deciding which dependencies deserve priority. Equipping hundreds of bases for prolonged isolation will compete with spending on weapons, personnel, and maintenance. The strongest case for the program rests on protecting indispensable operations first, rather than treating every installation’s needs as equal, which only adds to the logistical intricacy.

A military base that can withstand a blackout offers little comfort to nearby households if their own power stays off. Although the Pentagon’s plan protects national defense, it also exposes how much civilian life depends on infrastructure that cannot simply disconnect and carry on. Britain’s advice recognizes that governments cannot restore every service immediately, and that keeping basic supplies gives households some independence during those first days without requiring them to predict the next emergency.

The scale of the planning suggests the Pentagon is preparing for an adversary capable of disrupting American life far from any battlefield. Chinese hackers’ previous penetration of civilian networks gives that concern a concrete basis. A 90-day requirement does not mean officials expect an imminent attack. But it does suggest they are taking seriously the possibility that, in a future conflict, restoring power and supplies could take months.