Here’s what we know:
Two bombs went off near the finish line of the Boston Marathon yesterday. Three people were killed and 176 were wounded. The bombs did not use high-grade explosive material. No additional bombs have been found.
Here’s what we don’t know:
Who set the bombs. Why they were set. Whether more attacks are planned.
What we should do:
Investigate. Determine the answers to the questions. Continue to help the injured. Prosecute the guilty when we know who they are.
What we should not do:
Remember that the worst thing that we can do in response to acts of terrorism is to be terrified. We should be vigilant, but we should not do anything without evidence. Do not cancel public events without evidence of specific, credible threats. Do not begin requiring people to remove their shoes before entering sports stadiums. Do not assume anything about the perpetrators: nationality, numbers, or motivations. Do not give credence to conspiracy theories that the government is behind it (or any other conspiracy theories, for that matter).
Update: Charles Stross adds another recommendation: Stop following the news for a couple of days. I think he’s overstating the case a little bit, but in general it’s good advice. There will be very little new information in the next couple of days. Seeing the same limited information over and over, supplemented by alarmist speculation is not going to contribute to remaining calm and not taking hasty action.