in case you doubt (AI saved me a lot of time here)

Invention Secrecy Act: Under the Invention Secrecy Act, the U.S. government can prevent a patent from being granted if it deems an invention a threat to national security. This allows the government to withhold the invention from public disclosure and, in effect, control its use.

Defense Production Act (DPA): The DPA grants the president authority to direct private industry to prioritize government contracts, including for critical technologies. While not a direct seizure, it enables the government to compel production or access to essential resources, including advanced technology, during emergencies or wartime.

Military Acquisition and Reverse Engineering: Historically, the U.S. has actively acquired foreign military technology during conflicts. For example, during the Cold War, the U.S. recovered and reverse-engineered Soviet aircraft and missiles (like the MiG-15 and SA-2) to understand enemy capabilities and improve its own systems.

International Law and War Booty: In armed conflict, under the law of war, captured military equipment—including advanced autonomous weapon systems (AWS)—can be seized and used by the capturing state. While prize law traditionally applies to vessels, modern interpretations suggest that captured military technology, especially if it serves a legitimate military objective, may be lawfully taken and repurposed.

Government Use of Patented Inventions: Even if a private individual holds a patent, the U.S. government may use the invention without consent under the principle of "government use rights," especially when it serves national defense. The inventor cannot sue to stop the use, though they may be entitled to reasonable compensation.