By Mimi Hall, USA TODAY

Looking to prevent the next terrorist attack, the Homeland Security Department is tapping into the wild imaginations of a group of self-described "deviant" thinkers: science-fiction writers.

"We spend our entire careers living in the future," says author Arlan Andrews, one of a handful of writers the government brought to Washington this month to attend a Homeland Security conference on science and technology.

Those responsible for keeping the nation safe from devastating attacks realize that in addition to border agents, police and airport screeners, they "need people to think of crazy ideas," Andrews says.

The writers make up a group called Sigma, which Andrews put together 15 years ago to advise government officials. The last time the group gathered was in the late 1990s, when members met with government scientists to discuss what a post-nuclear age might look like, says group member Greg Bear. He has written 30 sci-fi books, including the best seller Darwin's Radio.

Now, the Homeland Security Department is calling on the group to help with the government's latest top mission of combating terrorism.

Although some sci-fi writers' futuristic ideas might sound crazy now, scientists know that they often have what seems to be an uncanny ability to see into the future.

"Fifty years ago, science-fiction writers told us about flying cars and a wireless handheld communicator," says Christopher Kelly, spokesman for Homeland Security's Science and Technology division. "Although flying cars haven't evolved, cellphones today are a way of life. We need to look everywhere for ideas, and science-fiction writers clearly inform the debate."

Bear says the writers offer powerful imaginations that can conjure up not only possible methods of attack, but also ideas about how governments and individuals will respond and what kinds of high-tech tools could prevent attacks.

The group's motto is "Science Fiction in the National Interest." To join the group, Andrews says, you have to have at least one technical doctorate degree.

"We're well-qualified nuts," says Jerry Pournelle, co-author of the best sellers Footfall and Lucifer's Hammer and dozens of other books.

Pournelle and others say that science-fiction writers have spent their lives studying the kinds of technologies and scenarios Homeland Security officials have been tackling since the department began operating in 2003.

"We talk to a lot of strange people and read a lot of weird things," Bear says.

At the Washington conference, Bear offered to put biometrics researchers in touch with movie special-effects experts. The experts might be able to help the government determine how to match the face of someone walking through an airport to a grainy photo of a known terrorist.

Bear's latest book, Quantico, is a sci-fi thriller that has FBI agents and a bioterrorism expert racing to hunt down a homegrown terrorist.

"We'll play 'What if?' with anything," says Sage Walker, an emergency medicine physician turned sci-fi writer and the only woman in the group. She says the discussions with government officials "tend to be very intense and far-ranging."

So are discussions between the writers. During a coffee break at the conference, Walker, Bear and Andrews started talking about the government's bomb-sniffing dogs. Within minutes, they had conjured up a doggie brain-scanning skullcap that could tell agents what kind of explosive material a dog had picked up.

The 9/11 Commission called the 2001 terrorist attacks a result of the government's "failure of imagination." For this group, Walker says, there's no such thing as an "unthinkable scenario."

Why offer their ideas to the government instead of private companies that pay big bucks?

"To save civilization," Ringworld author Larry Niven says. "We do it in fiction. Why wouldn't we want to do it in fact?"