It’s been an extraordinary week of fast-moving events — a week of tragedy, tears, anger and fear. Yet the bombs that on Monday shattered the joyful celebration of a storied event, the Boston Marathon, killing three people and injuring nearly 200, never blew a hole in the social fabric. Too many helping hands — heroic first responders, brave ordinary citizens — stood ready to hold it together.
Then swiftly followed brilliant police work by the FBI, and other law-enforcement agencies aided immeasurably by the tools of the modern age — surveillance cameras in public spaces and video and photos shot on cell phones and digital devices in the hands of spectators. Those images proved decisive.
By late Thursday, after the FBI released video and photos, the tips were pouring in and the suspects — Tamerlan Tsarnaev, 26, and his brother Dzhokhar, 19 — were on the run.