Could Russia really have helped thwart the Boston Marathon bombings?

When Tamerlan and Dzhokhar Tsarnaev bombed the finish line of the Boston Marathon a year ago, Russia and the U.S. were still at least frenemies. Now, as the two countries are increasingly at loggerheads over the situation in Ukraine, a new report has found that Russia withheld potentially critical information from the FBI that could have helped the U.S. nab Tamerlan Tsarnaev before the bombing, according to The New York Times.

"They found that the Russians did not provide all the information that they had on him back then, and based on everything that was available the FBI did all that it could," a senior American tells The Times. The report, from the inspector general of the intelligence community, has not been made public, but it reportedly largely exonerates the FBI. So what did Russia fail to do?

First, here's what Russia did do: In 2011, after Tamerlan visited the restive Russian province of Dagestan, Russian officials told the FBI that he "was a follower of radical Islam and a strong believer" and "had changed drastically since 2010 as he prepared to leave the United States for travel to the country's region to join unspecified underground groups," The Times reports.

Subscribe to The Week

Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.

SUBSCRIBE & SAVE

Sign up for The Week's Free Newsletters

From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.

From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.

Sign up

Based on these warnings, the FBI examined Tamerlan's school, criminal, and internet records, and interviewed him, his parents, and friends. When that turned up nothing, FBI agents in Moscow asked Russian intelligence for more information. Russia declined. After the bombing, Russia turned over some other information, like an intercepted call between Tamerlan and his mother in which they discussed Islamic jihad. According to the inspector general's report, that information could have given the FBI more legal authority to monitor Tamerlan.

That's a lot of what-ifs. It does sound like Russia could have been more generous with its intelligence, but it's also still kind of incredible that Russia and the U.S. were sharing the fruits of their spying at all. This final quote, from a senior U.S. official to The New York Times, kind of sums it up: "Had [the FBI] known what the Russians knew they probably would have been able to do more under our investigative guidelines, but would they have uncovered the plot? That's very hard to say." It always is with counterfactuals.