The United States Armed Forces

The United States Armed Forces grew from a ragtag Continental Army into the most powerful military in the world. The nation that was founded in suspicion of standing armies now maintains six branches — the Army, Navy, Marine Corps, Air Force, Coast Guard, and Space Force — with a global reach no other power has ever matched.

The early republic relied on a small regular force backed by citizen militias, wary of the threat a large army might pose to liberty. That changed slowly: the Navy and Marines were established in the founding era, West Point and Annapolis professionalized the officer corps, and each major war expanded the force before it shrank again in peacetime.

The World Wars and then the Cold War ended that cycle. After 1945 the United States kept a vast permanent military for the first time, unified its services under a new Department of Defense, and built the nuclear arsenal and global base network that defined its superpower status. President Eisenhower warned of the "military-industrial complex" this permanent establishment created.

Today the armed forces are an all-volunteer professional force of well over a million active members, funded by the largest military budget in the world. The institution the founders feared became central to American power — and to the debates over how that power should be used.