Here are a few of the most useful news and commentary pieces I've found on the Internet in relation to Monday's bombing attack on the Boston Marathon:
• The Boston Globe has removed its pay wall, at least for now.
• Until actual facts emerge, it's worse than useless to blame right-wingers, Muslims or any other reliably scapegoated group. Commentary from Nick Gillespie at Reason magazine and from Glenn Greenwald at the Guardian. (I like this Tweet from my friend Jeremy Weiland: "Thought experiment: imagine what explanation for the #bostonmarathon attack would be most disturbing to your personal political biases.")
• The Washington Post points out that terrorism in the U.S. has been declining.
• Bruce Schneier, a reliably-sane commentator on security matters, urges everyone to keep calm and carry on.
• If you want to help or learn more, ProPublica has put together a bundle of links.