The long-awaited report by House Republicans on Benghazi released Tuesday packed all the explosive punch of a 5-cent firecracker. Yes, it found a series of failings by the national security bureaucracy, but here’s what else it did: Cleared former Secretary of State Hillary Clinton of the absurd accusation that she somehow knew about the attack on the diplomatic compound in Libya before it happened and did nothing about it.

The GOP-led committee’s desire to find evidence of malfeasance by Ms. Clinton to support all the conspiracy theories surrounding Benghazi went unfulfilled. Had there been real facts to support it, surely this committee would have found it. After all, that was the panel’s real mission, despite the talk of concern about national security.

Instead, the minutely detailed, 800-page document produced by the committee assigned blame far beyond Secretary Clinton’s State Department. As the McClatchy news story declared, “Actions of the Pentagon, FBI and intelligence community were also critiqued.”

But we already knew that from the eight investigations that preceded this politically inspired probe. The report — a product of the longest Congressional investigation in memory on possible wrongdoing in the executive branch, longer than Watergate or 9/11 — went a bit further and deeper than the earlier ones, but the general outline was already known.

The primary finding is that Washington officials, confronted by the fact that something terrible was happening in Benghazi, engaged in a lot of dithering instead of the immediate reaction that could have saved lives. That produced a policy disaster that tarnishes everyone connected to it.

That is genuinely scandalous, and it should never have happened. But again, Washington’s failure became evident in the weeks immediately following the 2012 attack that killed U.S. Ambassador Chris Stevens and three American colleagues: Sean Smith, Glen Doherty and Tyrone Woods. It shouldn’t have taken yet another investigation to tell the American public what it had already been told.

Also evident, by the way — although congressional Republicans have been loath to admit it — is that legislators failed to appropriate funding for security at U.S. diplomatic posts around the world at the level the State Department had asked for earlier. That was a critical element of the Benghazi debacle for which Congress is wholly to blame.

In terms of the big picture, there were no startling new revelations, no bombshells. But then, that was probably never the intent. The purpose all along was clearly to prolong the controversy in the hope of finding something — anything — that would produce embarrassing headlines for former Secretary of State Clinton just before her expected nomination as the Democratic candidate for president.

In that regard, the committee can take some credit for unearthing one political dustup that is still ongoing, Ms. Clinton’s email scandal, but that hardly rises to a level that justifies the panel’s alleged public policy purpose. Nor is it likely to affect the outcome of the presidential election.

Is there some lesson here for the future? Only one that we’ve heard before: Congress should never use its investigative power for political purposes. It discredits the investigative process, discredits the members who take part in it and discredits Congress itself.

— The Miami Herald, June 28