World War III will be fought with computers, a former Homeland Security IT chief is warning. In fact, he said, preliminary salvos are already underway.Steven Cooper said foreign hackers are using automated programs to ping networks that control critical infrastructure such as bridges, dams, and nuclear plants-as well as systems that run the Department of Homeland Security itself-literally millions of times per day in an effort to break in.

"If there's World War III, it will be waged in cyberspace," said Cooper, who spoke this week at Pace University's Leadership and Service In Technology Award reception in downtown Manhattan. Pace tapped Viacom CIO Joe Simon as this year's winner. Simon spoke only briefly, while Cooper delivered the keynote.

Speaking just a stone's throw from where the World Trade Center buildings collapsed on 9-11, Cooper said the U.S. needs to better prepare itself to deal with attacks that will come not in the form of commandeered jetliners, but as silent assaults on computer networks that are essential to the economy and public safety.

"The nature of warfare is changing rapidly," said Cooper, who was Department of Homeland Security CIO during George W. Bush's administration and whose resume includes a stint as CIO of the American Red Cross. He's now a partner at consulting and investment firm Strativest, LLC in Burke, Virginia.

Cooper said that one way the U.S. can arm itself to fight the cyberwars is to make sure the country can recruit the best and brightest IT professionals from around the world, and keep them here. Visa restrictions imposed since 9-11 are making it more difficult for computer science and engineering students who study at top U.S. colleges to remain in the country. "Foreign nationals are returning home," said Cooper.

Not only does that deplete the pool of talent available to U.S. companies and public agencies, it means some foreign governments, like China and Iran, will have greater access to U.S.-trained experts for their own electronic espionage programs. "A very small minority of the students we train here will use what they learned against us," Cooper told me in a brief conversation after his keynote.

Why worry about a small minority? Because it took just a handful of terrorists to bring down the Twin Towers--a few hackers could do considerably more damage, without even crossing our borders, if they are able to gain control of the systems that run, say, a nuclear power station. Last month, I reported exclusively that foreign hackers broke into systems maintained at two U.S. Army posts.

The Pace event was held at The Bank of New York, about a block from Ground Zero. Afterwards, I exited the building and stepped into the Manhattan night. I gazed at the empty space where the towers once stood and felt glad we've got guys like Cooper on our side, and that they're speaking out.