In a speech on the Senate floor Tuesday, Senate Minority Leader Mitch McConnell posed a provocative question in the wake of the Boston bombings: Have Americans become complacent about the risk of terrorism?

“On 9/11, we were forever disabused of the notion that attacks like the one that rocked Boston yesterday only happen on the field of battle, or in distant countries,” McConnell (R-Ky.) said. “With the passage of time, however, and the vigilant efforts of our military, intelligence and law enforcement professionals, I think it's safe to say that, for many, the complacency that prevailed prior to September 11th has returned. And so we are newly reminded that serious threats to our way of life remain.”

President Obama on Tuesday felt compelled to remind Americans that they should report to law enforcement any package or situation that seems unusual. “This is a good time for all of us to remember that we all have a part to play in alerting authorities,” Obama said at a news briefing. “If you see something suspicious, speak up.”

Even the catchphrase “see something, say something” has become “background noise,” according to Michael Greenberger, director of the University of Maryland's Center for Health and Homeland Security.

“It's just a sense that since nothing’s happened since September 11th, the guard has been let down a bit,” Greenberger said in an interview. “The silver lining from this is they're going to be built back again.”

Americans still see terrorism as a high-stakes public policy issue, although it has almost disappeared from their list of the nation’s top problems. A Gallup poll conducted in early April and released Monday found zero percent of Americans volunteering “terrorism” as the country's most important problem. Terrorism ranked at 1 percent or below in six similar polls conducted before that Gallup poll, compared with above 20 percent in the year after the 2001 attacks on the World Trade Center and Pentagon.

Part of this stems from the fact that most Americans believe the country is safer since Sept. 11; two-thirds of respondents held that view in a Washington Post-ABC News poll in 2011.

Julian Zelizer, a professor of history and public affairs at Princeton University, said that the fact that Americans have not recently experienced a heightened state of alert shows that “life just normalized after the attacks and following the creation of a rather elaborate counterterrorism program.”

“That is the objective of effective policies,” Zelizer wrote in an e-mail. “That said, like before 9/11, it is clear that there are many areas of national security that still need work — from sporting events to ‘soft-target’ terrorism (broadly defined) in places of commerce like malls. This event is likely to prompt renewed attention to what needs to be done to strengthen our security, as much as possible, in those areas.”

Rep. C.A. Dutch Ruppersberger (D-Md.), ranking member of the House Select Permanent Committee on Intelligence, said in an interview that much of the challenge has been hidden from public view.

“But obviously, you are now going to see a swing. You’ll see high security at baseball games and at events where people gather across the country. And it will remind people that the best defense against terrorism is for people to stay alert and report what they see to authorities,” he said.

Sen. Orrin G. Hatch (R-Utah) said citizens and the government need to do more.

“Generally, we're an optimistic people in this country and we generally believe we're going to be all right, and that's what we want people to believe, but we also have to do a better job,” Hatch said.

The fact that major cities such as New York have been successful in heading off potential terrorist acts has allowed Americans to feel more secure, he said.

Sen. Dianne Feinstein (D-Calif.), who chairs the Senate Select Committee on Intelligence, challenged the idea that Americans had become less security-conscious.

“We’ve watched our inaugurals; we’ve put special effort into them. We have put special efforts into the World Series, at football games, at baseball games, at the Masters,” she said. “And yet, here are some people who picked a 25-mile run, which is very hard to guard. . . . I don’t believe we are complacent on security.”

House Homeland Security Committee Chairman Michael McCaul (R-Tex.) said Monday’s strike “shows we're still vulnerable.” McCaul recently met with police in New York and told members of his staff that he was amazed at how authorities there still seem to approach each day as if it could be Sept. 11.

“Now, do we want to change our everyday lives?” he asked. “No. but I think we need to recognize that we're still a country that needs to maintain a high level of security and balance that security as an open society.”

Scott Clement contributed to this report.

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