But more importantly, this air-breathing engine generates a very different signature from a rocket motor, meaning space-based surveillance assets might not be able to spot one as quickly or keep tracking it during flight, or even spot it at all for that matter. On top of that, prototype designs look much more like super-fast flying cruise missiles or drones, able to fly in more erratic ways well within the atmosphere, maybe even changing course in mid-flight relatively rapidly. This could make any such weapon more accurate, since it could make more corrections before impact, as well. A projectile flying at a mile a second would be too much to process in general for even the most fast-scanning surface- and airborne radars that exist at present, and even if they could be tracked, engaging something going that speed within the atmosphere represents a huge set of problems of its own.

All of these features have made the concept attractive within the Pentagon, as potential opponents field increasingly more powerful radars, surface-to-air and air-to-air missiles, and other weapons that could deny existing, more conventional American military forces from getting close to their objective in the first place. The U.S. military has collectively dubbed these threats as “Anti-Access/Area Denial,” or A2AD. Hypersonic weapons could be the key to breaking through these protective layers, including knocking down an enemy's integrated air defense system (IADS), during a crisis, maintaining America’s ability to hold its enemies under threat.

A hypersonic system would have significant benefits in a time-sensitive strike scenario, whether it be taking out a terrorist at a particular location or quickly knocking out vital enemy weapons or installations during a larger conflict. The immense speed of one of these craft could dramatically shrink the time it takes to go from first identifying any target to actually hitting it with a weapon, which in turns gives opponents significantly less time to notice they’ve been spotted and attempt to reposition, get into cover, or otherwise improve their defenses.