WHAT a world. And how it changes. It seems Russian authorities alerted their American counterparts a year ago about a potential terrorist (“a follower of radical Islam”) named Tamerlan Tsarnaev. It was the American intelligence agencies, principally the FBI but maybe with a little help from the CIA, that let the suspect slip through their fingers in a sequence of events worthy of Inspector Clouseau-with a supporting cast consisting of Mack Sennett’s old Keystone Cops.

It used to be said that “military intelligence” is a contradiction in terms, but our civilians don’t seem to be doing much better. The FBI did interview this suspect at one point. It asked him if he was a terrorist, he said he wasn’t, and that was the end of that. If you can’t trust a terrorist, who can you trust, right? Case closed. Till those explosions rocked Boylston Street, spreading death and destruction and leading to a shutdown of a major American metropolitan center. Just what terrorists love. They thrive on panic. Happily, the people of Boston remained calm and determined. An example for us all. As they have been since at least 1776.

Naturally, neither the FBI nor the CIA seems to have thought to alert the Department of Homeland “Security” about the threat the Russians had flagged for them. We seem back in the pre-John Ashcroft stage of American law enforcement. He was the attorney general during the first years of the Bush administration immediately after September 11th when the war on terror was being taken seriously.

Mr. Ashcroft did his best to erase the wall between American security agencies foreign and domestic, a wall that had left the country vulnerable to attack. For one American security agency might not know what the other was doing-by law! And so the perpetrators of 9-11 avoided detection. John Ashcroft, if you’ll recall, was roundly denounced at the time by the usual Bushophobes.

When he wrote his memoir of those events, Mr. Ashcroft titled it Never Again. But it’s now clear he spoke too soon. For not even the best security system can be any better than the human beings entrusted with its operation. When they make a movie of all this, perhaps the role of Robert Mueller, director of the Federal Bureau of Investigation, could be played by someone like Peter Sellers. Only this was no comedy.

Editorial, Pages 16 on 05/01/2013