Two tests in 2000 failed because of malfunctions by the rockets and their kill vehicles.

As a result, the "kill vehicle" got nowhere near the target.

In December 1998, its team lost the competition to build the kill vehicle.

The kill vehicle hurtled toward the missile but failed to hit it.

In an attack, boosters would release the kill vehicle more than 100 miles above earth.

The test was intended to try out only the kill vehicle.

Some of the biggest woes center on the kill vehicle itself.

The Pentagon has announced no plans to test the kill vehicle against such a stratagem.

In the second, "the kill vehicle did not respond to navigation commands."

The budget for the space-based kinetic kill vehicle is now $126 million.