In all instances, Biden relied on citing Article II executive powers and self-defense of U.S. forces, or the Authorized Use of Military Force. Congress has not declared war since 1942.

The Authorization for Use of Military Force is a joint resolution by Congress that gives the U.S. president the authority to leverage military force in a conflict.

Application of mechanics to the study of static equilibrium of rigid and elastic bodies. Topics includes composition and resolution of forces; moments and couples; equivalent force systems; free-body ...