The DoW urgently needs to organize its scattered subterranean warfare assets into a single unified organization. Ideally, a Direct Reporting Portfolio Manager (DRPM) for Subterranean Warfare, reporting to the Deputy Secretary of War. (The Department already uses this model for unmanned systems, critical weapons and Golden Dome.) This group would have three portfolios: Subterranean Resilience, Subterranean Sensing and Subterranean Defeat. The office would integrate validated requirements, experimentation, testing, acquisition, and fielding.
Subterranean Resilience
During the 2026 Iran conflict, Iranian ballistic missiles and low-cost drones hit U.S. installations across eight Middle Eastern countries. Hundreds of buildings and structures were damaged or destroyed. The Navy’s Fifth Fleet headquarters in Bahrain was among the installations hit hard. Iranian weapons damaged one E-3 airborne early-warning aircraft and five KC-135 tankers on the ground in Saudi Arabia. (The official inspector-general report documents the damage.) Despite thousands of successful interceptions, the attacks exposed the vulnerability of concentrated, above-ground assets.
The rapid redeployment of the B-1s from RAF Fairford in the UK after warnings of an Iran-linked threat (reported as a possible drone attack) made the point: unsheltered concentrated high-value aircraft are vulnerable even way outside the theater.
The assumptions the U.S. has made about air superiority, missile defense, aircraft dispersal, building hardening, and the survivability of concentrated forward bases were all flawed. While we were prepared for ballistic missiles and hostile aircraft, drone swarms combined with ballistic missiles saturated and got through our defenses.
Washington’s reaction has been to invest billions of dollars in counter-drone and missile defense systems. Yet public budget documents reveal no comparable effort to put vulnerable aircraft, fuel, command-and-control nodes, and munitions out of harm’s way – sheltered, underground (or in space). (Agile Combat Employment, dispersal, hardening, deception, shelters, and rapid runway repair were never designed for a combined drone and missile onslaught.)
The Pentagon has recognized for decades that underground facilities are among the most effective ways an adversary can blunt U.S. conventional superiority. It described that problem explicitly in 1999. Gaza and Ukraine should have made it abundantly clear.
China, Russia, North Korea, and Iran use underground facilities, dispersal, hardening, and deception to make their own high-value assets harder to find, assess, and disable. We need to underground assets that cannot be quickly replaced: command posts, comms nodes, ammunition, fuel distribution points, repair facilities, key power systems, maintenance spares, and high-value aircraft or drones. The department needs an integrator that coordinates resilience across the Military Departments, Joint Staff, combatant commands, defense agencies, and intelligence community and provides Subterranean Resilience.
However, resilience is only one part of subterranean warfare.
Subterranean Sensing and Defeat
The U.S. needs to know where adversaries' underground facilities are located, and the internal layout of those facilities. Today, these bespoke exquisite systems for tunnel detection, robotic mapping of accessible tunnels, Hard and Deeply Buried Targets (HDBT) characterization, and target defeat are siloed in organizations scattered across the DoW. Most of these systems still require boots on the ground. Once a target is found, Combatant Commands need an integrated system that can characterize and destroy these targets, without first gaining physical access. Today, for the deepest facilities that means bombing from the air. Iran is the case in point.
Background. Iran's route to a nuclear weapon is by enriching uranium. Natural uranium is composed of 0.71% uranium-235 (U235) and it’s only the U235 that is used to build a bomb.
Iran uses centrifuges to separate U235 and increase its concentration (enriching it.) One centrifuge won’t do much, but connecting thousands of centrifuges together into cascades and running them for months can produce pounds of U235.
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