The United States is on the “wrong side” of the ballistic missile defense (BMD) cost curve because it shoots down inexpensive rockets with very expensive ones, according to a key officer.

U.S. Northern Command (NORTHCOM) chief Adm. William Gortney on Tuesday laid out a game plan for the United States to get on the correct side of the cost curve. He said the United States needs to look at the entire kill chain of these ballistic missiles and “keep them on the rail” through kinetic or non-kinetic means or through deterrence.

A Ground-Based Midcourse Defense Interceptor launch. Photo: Missile Defense Agency.
A Ground-Based Midcourse Defense Interceptor launch.
Photo: Missile Defense Agency.

Though Gortney defended the U.S.’ BMD capabilities to reporters at the Pentagon, he said the Missile Defense Agency (MDA) needs to improve its discrimination sensors to provide high confidence and detect objects in space. The United States, he said, also needs to improve the lethality of the kill vehicles, as well as upgrade and maintain the kill vehicles it already has.

Gortney said the United States needs to start knocking down adversaries’ missiles while in the boost phase, the first of three missile defense phases, as opposed to focusing on the “expensive” midcourse phase. The boost phase defenses can defeat ballistic missiles of all ranges, including ICBMs, but it is the most difficult phase in which to engage a missile, according to MDA.

Although the missile is easiest to detect and track in the boost phase because its exhaust is bright and hot, missile defense interceptors and sensors must be in close proximity to the missile launch. Early detection in the boost phase allows for a rapid response and intercept early in its flight, possibly before any countermeasures can be deployed, according to MDA.

The midcourse phase begins when the enemy missile’s booster burns out and the missile begins coasting in space toward its target. This phase can last as long as 20 minutes, allowing several opportunities to destroy the incoming ballistic missile outside the earth’s atmosphere. Any debris remaining after the intercept will burn up as it enters the atmosphere, MDA said.

The terminal phase is very short and begins once the missile reenters the atmosphere. It is the last opportunity to make an intercept before the warhead reaches its target. Intercepting a warhead during this phase is difficult and the least desirable of the phases because there is little margin for error and the intercept will occur close to the intended target, according to MDA.

U.S. midcourse phase defenses include the Ground-Based Midcourse Defense (GMD) element based at Vandenberg AFB, Calif., and Fort Greely, Alaska; and the Navy’s mobile ship-borne Aegis BMD element. Terminal phase defenses include the Terminal High Altitude Area Defense (THAAD), the Aegis BMD near-term Sea Based Terminal Defense capability using SM-2 Block IV missiles and the Army’s Patriot Advanced Capability-3 (PAC-3) missiles deployed from the Patriot Air Defense System.