Before last week's hearing on the attack in Benghazi, Libya, Republicans in Congress promised explosive new details about the administration's mishandling of the episode. Instead, the hearing showed, yet again, that sober fact-finding is not their mission. Common sense and good judgment have long given way to conspiracy-mongering and a relentless effort to discredit President Obama and former Secretary of State Hillary Rodham Clinton.

The attack on the lightly protected consulate that killed Ambassador J. Christopher Stevens and three other Americans was tragic, and Americans should know the full story. The most authoritative account, completed in December, came from an independent inquiry, led by two respected and now retired officials — Thomas Pickering, a former deputy secretary of state, and Adm. Mike Mullen, a former chairman of the Joint Chiefs of Staff.

Their report was unsparing in concluding that "systemic failures and leadership and management deficiencies at senior levels" in the State Department's bureaus of diplomatic security and near eastern affairs resulted in a "security posture that was inadequate for Benghazi and grossly inadequate to deal with the attack that took place." Clinton took responsibility for the security failures when she testified at a congressional hearing in January.

Last week's hearing, led by Rep. Darrell Issa, R-Calif., who is chairman of the House oversight committee, featured three witnesses who testified about those failures. One of them, Gregory Hicks, the No. 2 official in Tripoli, was at the embassy the night of the Benghazi attack. He said he was later demoted for raising questions about how the incident was handled, a charge the State Department denied.

The hearing did not prove anything like an administration coverup or other hysterical allegations of crimes equal to Watergate that some Republicans have alleged. Republicans have held numerous hearings and briefings on Benghazi and are threatening to hold even more. It is a level of interest they did not show during George W. Bush's administration when there were 64 attacks on American diplomatic targets or in the years they spent cutting back diplomatic security budgets.

The real scandal is that serious follow-up on security in Libya is going unaddressed. Congress needs to make sure that State Department budgets for personnel and security improvements are sufficient and that security reforms are put in place as soon as possible. The Senate should move quickly to confirm the ambassador, Deborah Jones, whose hearing was last week.

Congress and the Obama administration also need to pay more attention to what's happening in Libya in general. After helping opposition forces oust Moammar Gadhafi, the United States seems to have lost interest. That is a huge mistake as militias threaten the country's democratic transition and stability. That surely is not an outcome that Ambassador Stevens would have wanted.