During the second Gulf War, I was an Air Force colonel. I routinely flew on different aircraft to familiarize myself with their capabilities. One day I was aboard an intelligence aircraft where each crew member was surrounded by complex gear.

A young major showed me his computer screen. "That's a chat screen, Sir," the soldier said. "We use it to relay enemy information to the crew. It's like instant messaging."

Nodding, I moved down the line. Flashing on an airman's screen several feet away was this warning: "Heads up! The colonel's on the way!"