An inquiry into whether U.S. intelligence agencies could have done more to help prevent the Boston Marathon bombing is just getting started. But America's top spy is already convinced that the deadly April 15 attacks do not represent an intelligence failure.

As Bryan Bender of the Boston Globe first reported, the inspector general overseeing the 16 U.S. spy agencies will conduct a "broad review" of how the intelligence community handled whatever information it had about the bombings.

That review did not come at the behest of James Clapper, the director of national intelligence, the nominal boss of those spy agencies. Shawn Turner, a spokesman for Clapper, says it's an independent initiative of the Intelligence Community Inspector General along with the internal watchdogs for the FBI and the Department of Homeland Security.

Yet before the inquiry has concluded, Clapper is satisfied – as he first said last week, before any review even got started – that the intelligence agencies didn't drop the ball on Boston.

"Director Clapper believes that every agency involved in collecting and sharing information prior to the attack took all the appropriate steps," Turner emailed Danger Room. "He also believes that it is prudent an appropriate for there to be an independent review of those steps to ensure that nothing was missed."

Clapper's remarks carry the impression that there's little the factual inquiry can tell him that will change his mind. Inspectors general are supposed to be independent; rarely do the heads of their agency publicly announce conclusions about the subjects of ongoing inquiries.

The review does not have a broad mandate. "It is limited to a review of the handling of information related to the suspects prior to the attack," Turner said, adding that it is "not an investigation."

The FBI has acknowledged that it interviewed deceased bombing suspect Tamerlan Tsarnaev in 2011 after receiving a tip Russian intelligence that he was an Islamist extremist. When it didn't find information about anything illicit he had done, it dropped the issue. But on a tip from that foreign intelligence agency, the CIA lobbied to put Tsarnaev's name in a government database – albeit one containing the names of half a million people, and which does not authorize law enforcement to take action. The Department of Homeland Security learned that the elder Tsarnaev was traveling to Russia in 2012 – which investigators suspect might be a critical moment for his radicalization – but not upon his return to the United States.

The intelligence community is under open criticism in the media for not properly handling what little it knew about Tsarnaev. Sen. Richard Burr (R-N.C.), a member of the Senate intelligence committee has noted that the Russians passed on several warnings about Tamerlan Tsarnaev; but few Senators on that committee have said they consider U.S. spies to have failed on the case.

"I think there have been some stonewalls and some stovepipes reconstructed that were probably unintentional," the panel's vice chairman, Sen. Saxby Chambliss (R-Ga.), said last week, "but we have to review that."

Clapper preempted the criticism last week. Thus far, the FBI appears to have contacted Tsarnaev and found nothing to build a case around or authorize further surveillance. Clapper warned that it's not possible to determine the precise moment that people radicalize – especially to the point where they're prepared to commit a violent action – and added that such determinations would require a more intrusive surveillance and domestic-security apparatus than Americans might be willing to tolerate.

Obama said that he's ordered his counterterrorism team to examine "what more we can do" about the threat of self-radicalized individuals in the U.S. unconnected with any known extremist group. "All this has to be done in the context of our laws [and] due process," Obama cautioned.