The Pentagon’s secretive research agency says new advances are needed to counter adversary air defenses, along with innovative manufacturing techniques that can produce hypersonic weapons affordably and at scale.

DARPA is developing a hypersonic cruise missile in response to the Pentagon's concerns that American missiles are vulnerable to enemy air defenses.

The Pentagon’s secretive research agency says new advances are needed to counter adversary air defenses, along with innovative manufacturing techniques that can produce hypersonic…