The United States Air Force has provided a peek at one of the weapons expected to help modernize U.S. nuclear deterrence.
The Air Force released an illustration in early June 2025 of the Raytheon-built AGM-181A strategic-armed cruise missile. The weapon is a priority for the service’s Global Strike Command, a component of U.S. Strategic Command (USSTRATCOM), which is responsible for nuclear deterrence.
The AGM-181A, or Long-Range Standoff Weapon (LRSO), is expected to be a key capability for the upcoming B-21 Raider stealth bomber and will also be carried by the venerable B-52H Stratofortress. The LRSO will replace the only nuclear-armed U.S. cruise missile currently in service, the AGM-86B Air Launched Cruise Missile (ALCM), according to military news website The War Zone (TWZ).
The B-21 is in line to replace the B-1 Lancer and B-2 Spirit strategic bombers. It will have a crucial role in the modernization of the U.S. nuclear triad, which consists of land-based intercontinental ballistic missiles (ICBM), ballistic missile submarines and strategic bombers.
Gen. Anthony Cotton, Commander of USSTRATCOM, told the U.S. Senate Armed Services Committee (SASC) in March 2025 that the LRSO is an important part of next-generation deterrence. “The LRSO weapon will provide the President with flexible and scalable options capable of penetrating and surviving against advanced air defenses — a key attribute and critical component to all USSTRATCOM operational plans,” Gen. Cotton said.
The LRSO illustration’s release highlights the weapons program’s progress, according to Tyler Rogoway of TWZ. “If this first rendering is any indication, LRSO has moved well forward in its development, and we are likely to hear more about it and finally see it in full in the not-too-distant future,” wrote Rogoway, who noted that such depictions commonly omit details for security reasons.
Reports in 2022 stated that the LRSO had made nine successful flight tests — deploying from the B-52H, according to The Aviationist website. In 2024, then-Air Force Service Acquisition Executive Andrew Hunter told a U.S. Senate committee that the LRSO was on track to meet its timeline, according to the website. “The missile has been expected to begin entering operational service toward the end of the decade,” Rogoway wrote.
The LRSO will carry an updated W80-4 thermonuclear warhead, according to the National Nuclear Security Administration. It belongs to the “larger Long Range Strike family of systems, which includes the B-21 as its centerpiece, as well as new command and control, space-based support assets, weapons, communications, and other technologies,” according to Rogoway.
Unlike ICBMs, bombers such as the B-21, armed with weapons such as the LRSO, can be “forward deployed, held on alert, or recalled midmission, key tools in preventing miscalculation during crises,” the website Interesting Engineering wrote in June 2025.
Gen. Cotton summarized the importance of having such a capability in 2024 remarks to the SASC: “LRSO is absolutely critical for my mission set,” he said.