We now know who authorities believe placed the bombs that killed three spectators at the Boston Marathon, maimed dozens more and brought terrorism back to our shores.
But we should be cautious about jumping to conclusions about the motives of the two suspects, ethnic Chechen brothers who apparently came to America a decade ago.
Some reports quickly speculated that there could be a link to the separatist war in Chechnya or to radical Islam. But as we've seen time and again through this entire week, too many breathless reports have turned out to be completely wrong.
During a chaotic, violent night in the Boston area that claimed the life of a police officer at MIT, the older brother, 26-year-old Tamerlan Tsarnaev, died early Friday after a shootout with law enforcement. Friday night in a Boston suburb, 19-year-old Dzhokhar Tsarnaev was taken into custody after a daylong, door-to-door search by thousands of officers that virtually locked down a region of 1 million residents.
Whatever drove them to commit this atrocity, the finish line of the marathon was almost certainly targeted for maximum mayhem and attention. It turns out that choice also produced the most significant break in the investigation. Precisely because of the area's prominence, there were hundreds of images from video footage and photographs. They led to the identification of the suspects and the FBI's release on Thursday of their photos and a video.
Monday's bombing is a sobering reminder that while security measures and counterterrorism efforts here and around the globe have thwarted attacks, determined terrorists can still strike. Authorities believe the bombs were crude devices common pressure cookers filled with nails and ball bearings with how-to instructions widely available online.
We can be vigilant, but we can never be entirely safe and we must send a clear message that we won't sacrifice our liberties.
At an interfaith service Thursday in Boston to mourn the dead and comfort the injured, President Barack Obama praised the people of Boston for demonstrating that the city's strength against adversity isn't just a point of historical pride. He also struck a defiant note that Americans will not be cowed.
"We may be momentarily knocked off our feet, but we'll pick ourselves up," the president said. "We'll keep going. We'll finish the race."
Americans will not soon forget the images of the explosions and the injured sprawled on bloodstained pavement. What should also be remembered is that when the bombs exploded, many people police officers, runners, volunteers, bystanders did not flee for their own lives, but ran toward the victims to offer what aid they could.
That says volumes about America's resolve. It is our most profound response to terrorists.