PROVIDENCE — The government is wasting billions of dollars on fruitless antiterrorist tactics when what’s needed is more old-fashioned police work, a visiting security expert said yesterday.

The expensive and invasive high-tech surveillance schemes and armed guards at airport won’t block terrorist attacks, said Bruce Schneier, because the terrorists can simply go elsewhere.

If we guard the Super Bowl, the terrorists can attack a playoff game instead. Or a shopping mall. Or trains, the way they did in Spain, where more than 190 people died and 1,900 were injured in March 2005.

Schneier is the founder and chief technology officer of Counterpane, an Internet security company in Mountain View, Calif. The company was recently bought by BT Group PLC, the former British Telecom.

He is the author of five books, including Applied Cryptograph and Beyond Fear, which he describes as a book about “how we all can think sensibly about security.”

Right now, he thinks, we aren’t thinking, or acting, very sensibly about it.

Trying to guess what might be attacked and then guarding it, he said, is hopeless. “We cannot defend all the targets. It’s the wrong way to think.”

“Fundamentally, this is a game we can’t win,” he said. “We should stop playing it. It’s a stupid game,” where we decide what to protect, post guards, and leave terrorists to go elsewhere if they want to attack.

“Exactly two things have made our air travel safer since 9/11,” he said. “The first one was reinforcing the cockpit door, and the second one was convincing passengers they have to fight back. Everything else has been a waste of money.”

“All those [airport] screeners do, the reason they’re there, is they stop the sloppy and the stupid,” he said.

The country should focus on two points, he said: “Catch the bad guys while they’re still planning the attack, and at the end, emergency response — deal with the aftermath of whatever it is that happened.”

“It’s not about protecting the Super Bowl. It’s about going after the bad guys, their funding, their organization, their travel,” he said, by relying less on gadgets and more on smart investigators with good intelligence.

He would drop all of the federal government’s broad surveillance projects, “all these listen-to-everybody’s-phone-call kind of nonsense. It’s too much money, and too little return.”

The same goes for imposing a universal identification card on everybody in the country or requiring photo identification cards for access, the way some office buildings do.

“Every 9/11 terrorist had a photo ID,” Schneier said. “The Unabomber had a photo ID. The D.C. snipers had a photo ID. We’ve all got them.”

Antiterrorism successes have come, not through broad surveillance, warrantless eavesdropping or data-mining, he said, but rather through “old-fashioned police and intelligence work. That’s what will be successful.”

When he considers a program like REAL ID, the national identification card plan that President Bush signed last year, he said, “I think, how many FBI agents could I buy with that $11 billion?”

Schneier said that the way most of us ought to think about terrorism is, not at all. It’s not a threat; it’s irrelevant. The real threats are things such as traffic accidents and domestic violence, not terrorist attacks.

The more we worry about terrorism, the more the terrorists succeed, he said.

“The point of terrorism is to cause terror,” he said. “If we refuse to be terrorized, we deny them their victory.” As things are now, he said, “We’re doing their work for them.”

Similarly, he said, politicians who play on the terror issue are really helping the terrorists. “Refuse to vote for people who terrorize you,” he urged.

Unfortunately, he said, a politician following his prescription might not win office. “Doing the right thing would not get you re-elected,” he said, because it wouldn’t look active enough. “Action looks better than inaction, even if it’s running around in circles.”