Six hours north of Anchorage, Alaska, lies a sprawling, snow-covered military base called Fort Greeley. Three thousand miles to its south, hidden outside Lompoc, California, is another major installation—Vandenberg Air Force Base.
The two bases are linked by a unique security objective: to destroy nuclear-tipped missiles bound for the United States, should they ever be launched from North Korea, Iran, or another hostile state.
Known as “Ground-based Midcourse Defense” (GMD), the system’s basic premise is simple: incoming warheads are tracked by radar and satellite and destroyed by defensive “interceptor” missiles, launched from the bases in Alaska and California—an arrangement sometimes described as “hitting a bullet with a bullet.”
The Union of Concerned Scientists has analyzed the technical and political aspects of missile defense for more than three decades. Though the idea of a missile shield may sound attractive, today’s homeland system is hugely expensive, ineffective, and offers no proven capability to protect the United States—and no credible path forward for achieving success.