The hotels targeted in Jordan all bear the names of American companies, and that raises this question: Could it happen here?
Within hours of the bombings in Jordan, New York City positioned police patrols around big downtown hotels in a highly visible show of force.
"We have to react quickly to world events," says New York police Commissioner Raymond Kelly. "We don't know when there is a bombing someplace else in the world, whether or not it's part of a conspiracy, a bigger plot."
So far no sign of any connection between the Jordan bombers and anyone here.
But President Bush, expressing condolences at Jordan's embassy, said it's a horrifying reminder:
"We face an enemy that has no heart, an enemy that is defiling a great religion," he said.
Could similar bombings happen here?
Clearly, yes, says Homeland Security Secretary Michael Chertoff.
"A lot of people say it's not a question of if, but when," he says. "And I think that we have to assume that the enemy will continue to try to attack us."
Security experts cite several reasons why it hasn't happened yet, including:
- More comprehensive terror watch lists.
- Extensive border checks of visitors to the U.S.
- Closer monitoring of the sale of potential bomb components such as fertilizer.
- Aggressive investigation of potential U.S. terror cells.
- More successful assimilation of Muslim immigrants.
Chertoff agrees about the importance of assimilation.
"When people feel there's a sense of opportunity, a sense of equality, that removes one of the bases in which suicide bombers begin to kind of emerge," he says.
Still, the FBI says one sobering lesson of its study of security in Israel is that suicide bombers don't fit any profile. They are men and women, young and old.
And many officials offer one other explanation for why no suicide bombers have struck the U.S. since 9/11 — and that's luck.