That didn't take long.
Just over three days.
About 75 hours for the FBI to nail down Dzhokhar and Tamerlan Tsarnaev as the chief suspects in the Boston Marathon bombing. Tamerlan, 26, the elder of the two brothers, is dead. Chances are that soon Dzhokhar, 19, will be captured or dead, too.
The reason: street cameras.
Without that video footage, who knows when or if the alleged Chechen terrorists would have been caught. Who knows if they would have struck again before being taken down.
Once those images went up on television screens, though, they didn't stand a chance. The moment their faces were aired, a couple of hundred million Americans were on the lookout for them -- all because of video cameras.
Those cameras are among the heroes in the Boston story.
Street cameras leave many of us with mixed feelings, though. Truth be told, I don't really like them. Everyday I see more and more cameras hidden in ceilings, doorways and wall crevices in New York City and they freak me out a little. I make it a game sometimes to see how many I can spot between Grand Central and my office three blocks away. Depending on which way I walk, there are at least 50, and I'm probably missing half of them.
It's not that I'm afraid of being caught doing something wrong on them -- I'm too old to pull off a bank job -- it's that they scare me about what the future will look like. It frightens me to think what those cameras and other surveillance tools could be used for by a government not as benevolent as the one we have today. And I'm not one of those paranoid types; just an observer of history.
But for now, in the wake of Boston, Mike Bloomberg, Police Commissioner Ray Kelly and other advocates of ubiquitous security cameras are looking mighty smart. In light of Boston, even the privacy advocate in me can understand Bloomberg's call for thousands more cameras -- and even security drones.
But the Boston story will give way to others. And that's the concern. What will the story line be next year, or 10 years from now, or 100?
Already, we have almost no privacy in America. Every keystroke on a computer can be followed. Our phone conversations can be monitored. Our every move can be tracked by the phones we carry. One can only imagine what power the technological advances in the next century will offer those with an interest in our actions and whereabouts.
The classic response is if you have nothing to hide, what do you have to worry about? That's a good rejoinder in today's world. But it naively assumes that government will always be the good guys, where history emphatically suggests it may not.
But for today, we should cheer Boston's cameras for helping identify these two allegedly murderous creeps -- and breath a sigh of relief that American democracy is alive and well.
William F. B. O'Reilly is a Newsday columnist and a Republican political consultant.