A slew of new technologies may give the American military non-lethal ways to slow down terror incursions in Iraq: A fast-hardening foam could render munitions stockpiles useless; a portable netting system could stop vehicles in their tracks; and a microwave-like "pain ray" could scatter a crowd without a drop of blood being spilled.

But there are still a number of technical and bureaucratic hurdles these systems have to leap before they make it into Iraq. The foam and the netting have to go through the long, hard slog that is the Pentagon's buying chain. The pain-ray delivery system must be shrunk down to fit on the back of a Humvee. And, oh yeah, military researchers want to make sure it doesn't cause cancer or anything, either.

Today, U.S. forces do have a few non-lethal weapons--devices that are designed to hurt, not to kill--in their arsenal. Some of these have been distributed to Iraq, including electricity-firing tasers, rubber bullets and old-fashioned riot batons.

But "the state of the art for non-lethal is primitive," said Charles "Sid" Heal, an authority on non-lethal weapons who is a commander in the Los Angeles County Sheriff's Department. "There's nothing out there with what the military considers sufficient range providing adequate protection against a lethal countermeasure." Rubber bullets, flash-bang grenades and other non-lethal weapons travel only a few hundred feet.

But the pain ray being developed by the Air Force Research Laboratory, with a reported range of more than 700 yards, could make the grade. Officially designated the Active Denial System, the system fires millimeter-wave electromagnetic energy--like microwaves but in a different bandwidth. Penetrating just a 64th of inch beneath the skin, the waves feel "like a hot iron on you," Heal said.

The burning sensation is bad enough that people have to run away from them, quick. And that causes mobs to break up in a hurry. It's no wonder, then, why Heal calls the ray the "Holy Grail of crowd control."

My Chicago Tribune article has details.