In August 2024, the Army rewrote the rules for how it moves fuel, ammo, food, and parts to the warfighter. The revised FM 4-0 changed every supply chain assumption in the force. It tells sustainment commanders to plan as if their units are being watched, engaged, and contested across every domain, as the baseline for every plan.
That is a supply chain problem stated in military language. The network that moves what the warfighter needs must now assume it is under attack at every node, every route, every moment.
What changed in the operating environment?
The assumption of a safe rear has collapsed, and every node in the supply network now has to be planned as a target.
For decades, the chain ran the other way. The U.S. moved supplies through open sea lanes, safe air routes, and guarded ports. Fuel, ammo, food, and medical gear flowed on fixed routes from factories to the front. The belief was that no enemy could threaten the network at scale.
That belief was the historical exception. Martin van Creveld’s Supplying War, the standard reference on military logistics taught at war colleges for almost fifty years, traced campaigns from Wallenstein to Patton and showed that logistics, not strategy or tactics, set the outer edge of what armies could do. Contested movement was the baseline. The uncontested decades the U.S. enjoyed after the Cold War were the anomaly, and that window has closed. The Joint Concept for Contested Logistics names the new reality. Sustain the joint force when an enemy contests every domain, from the homeland to the point of contact. Move supplies when convoys are targets. Forecast demand when nodes go dark. Cut fuel needs when every convoy draws fire. Track stock without signals the foe can exploit. Officers have named these problems and begun reshaping Army sustainment to meet them.
How do the warfighters and the law define it?
Gen. Randall Reed of USTRANSCOM puts it in one line. His command is now “fighting to move, instead of moving to fight.”
Reed drew the line between disruption and targeting this way: “From a logistician standpoint, anything that gets in the way of doing what you’ve been asked to do, we tend to look at that as contested. But when it comes to defense, there’s a more consequential and deadly piece to that, when you have an actor or actors that intend to disrupt or destroy that.”
Congress wrote that into law in two places. 10 U.S.C. § 2926(h) defines the contested logistics environment as one where an adversary “directly targets logistics operations, facilities, and activities” across all domains. The Senate Armed Services Committee’s FY2026 NDAA goes further, defining contested logistics as operations “under conditions in which an adversary or competitor deliberately seeks or has sought to deny, disrupt, destroy, or defeat friendly force logistics operations.”
What does this mean for industry partners?
If the warfighter’s chain is contested at every node, then every firm that touches that chain sits inside the blast radius. Ports, carriers, third-party logistics providers, fuel suppliers, parts makers, data providers, software vendors, and the tier-three shops most primes have never met. A jammed GPS signal at a commercial port is a defense problem. A cyber intrusion at a carrier is a defense problem. A single-source ball bearing in a small Ohio shop is a defense problem. The line between commercial strength and military readiness has thinned. The next phase of the Contested Logistics work is aimed at that line: mapping where commercial networks carry defense load, pricing the risk those networks now hold, and building the joint work that closes the gap before the fight, not during it. Industry partners who see this now will help shape the work. Those who wait will inherit whatever the first movers design.
FM 4-0 told sustainment commanders to assume the chain is always contested. That assumption rewrites every supply chain decision the military makes, and every commercial decision that touches it.
Sources
Department of the Army. FM 4-0, Sustainment Operations. August 2024. armypubs.army.mil
Martin van Creveld. Supplying War: Logistics from Wallenstein to Patton. Cambridge University Press, 1977 (2nd ed. 2004).
Joint Chiefs of Staff. Joint Concept for Contested Logistics. 2022. jcs.mil
Maj. Jon Michael King. “Contested Logistics Environment Defined.” Army Sustainment. February 2024. army.mil
Maj. Gen. Mark T. Simerly, Col. Marchant Callis, and Maj. Ryan J. Legault. “Transforming Army Sustainment to Contend with a Contested Logistics Environment.” Army Sustainment. February 2024. army.mil
10 U.S.C. § 2926(h), “Operational Energy.” uscode.house.gov
Senate Armed Services Committee. FY2026 National Defense Authorization Act, Contested Logistics provision. 2025. congress.gov
Gen. Randall Reed, USTRANSCOM Commander. Quoted in “Transportation Command’s Gen. Randall Reed on contested logistics.” DefenseScoop. August 2025. defensescoop.com