Lawrence Wein is a low-key, affable guy, considering he spends his time thinking about things that would give other people the willies.

Wein, 48, is a Stanford Graduate School of Business professor who teaches operations management. But his work includes evaluating terrorist threats and how to stop them.

He became interested in terrorism after 9/11. He has evaluated the threat of anthrax and how to protect U.S. Postal Service employees, testified before Congress on the inadequacy of a plan to use fingerprints from only two fingers for identification, and has written op-ed pieces in the New York Times about the lack of port security and the threat of bioterrorism to the country's milk supply.

Some people are listening to what he says.

The government adopted the 10-fingers fingerprint plan after his testimony, and Washington, D.C., has a plan in place to protect its postal workers that other cities are now looking at, too.

But it is the lack of security at U.S. ports that may be the most troubling threat of all.

Only 6 percent of the thousands of 40-foot-long containers off-loaded at U.S. ports every year are flagged for inspection.

Time magazine recently reported that the country has spent $18 billion since 9/11 in making airports more secure but has spent only $630 million to protect the ports. A study last year by the Department of Homeland Security and the Coast Guard concluded that 70 of the nation's ports are vulnerable to terrorism.

The worst fear is that one of those 40-foot-long containers will have a nuclear bomb inside.

"I've tried to focus on the handful of ways terrorists could create hundreds of thousands of casualties, and thankfully there are just a handful," he said. "A nuclear weapon going off in a U.S. city is the worst scenario, but they all cause concern."

Port security is weak, he said, but others are realizing that, too. Oakland recently became the first U.S. port to check all containers for radiation.

Wein will go to Long Beach, Calif., for an April 21 state Assembly committee hearing on port security.

Wein testified before a Congressional committee on the fingerprint issue in the fall of 2004 in what turned out to be a highly charged political session. It was just five weeks before the presidential election, and he had been asked to testify by Democrats on two committees holding joint hearings on security and terrorism issues. The Republicans didn't want any negative headlines.

"It was almost like being the middle of a murder trial," he said. "One side was throwing softball questions and the other side was trying to discredit me."

When the Democrats wanted to start asking him about port security, the Republican committee chairman ended the hearing.

"I kind of view my job as educating policymakers," he said. "Even if things don't change, I still end up educating them most of the time."

His Stanford colleagues respect his work because they know he is dealing with serious issues. So far, he hasn't gotten any clever nicknames from his colleagues.

But his wife, Anne, was recently at a Stanford event and one staff member referred to her as "Dr. Doom's wife." They live in Palo Alto, with children at Paly, Jordan and Walter Hays schools.

Wein never expected to be dealing with terrorism issues. He teaches the business school core course in operations management. His doctorate degree from Stanford is in operations research, which uses mathematical models to help in decision making.

But even before 9/11 he was looking at health care issues such as AIDS and Alzheimer's and how to allocate medical resources. After 9/11, he shifted to evaluating biological and other terrorist threats.

He is pleased his testimony contributed to a change in fingerprint policy.

"The system sometimes works," he said.

Wein is now studying another terrorism-related issue. But since his study isn't published yet, the work can't be revealed publicly.

Some things do give other people the willies, and his new research likely will.