WHILE CONGRESS continues to spar over a pointless re-investigation of the attack on the U.S. mission in Benghazi, in the real world of Libya events have taken another turn for the worse. A retired Libyan general who spent years of exile in Northern Virginia has launched a campaign against the Islamist militias that control parts of Benghazi and Tripoli as well as against the national parliament. The result is that Libya is sliding from political chaos toward a full-blown civil war.

Khalifa Hifter, a nationalist general who became a U.S. citizen, may look superficially appealing to some in the West. His military campaign, which he calls Operation Dignity, is aimed squarely at the Islamist militants who in the past year have pushed aside the secular forces that attempted to lead Libya toward democracy after the fall of dictator Moammar Gaddafi. His first strike was against the Benghazi-based Ansar al-Sharia militia, which is believed to have played a central role in the September 2012 attack on the U.S. mission. Some in Libya are comparing Mr. Hifter to Abdel Fatah al-Sissi, the general who led the coup against Egypt’s Islamist government and has since violently repressed the Muslim Brotherhood.

Mr. Hifter, however, is no more likely than Mr. Sissi to restore stability to his country. His melange of forces, including parts of the air force and navy, as well as several militias, face strong opposition from Islamist militias and from hardened fighters from the city of Misurata, a focal point of the rebellion against the Gaddafi regime. Having helped bring Mr. Gaddafi to power in a 1969 revolution and later formed an opposition movement with the help of the CIA, Mr. Hifter appears to have little in the way of a political program other than eliminating the Islamists. “We see that confrontation is the solution,” he said last week in an interview with The Post.

Libya is the base for some extremist groups with links to al-Qaeda, and military action will probably be needed to neutralize them. But the country’s broader Islamist political movement cannot be wiped out by a military campaign. Instead, as a joint statement by the United States and European Union governments on Friday noted, “the process leading to a peaceful transition of power should be based upon broad consensus.” The statement rightly distanced the West from Mr. Hifter’s movement, rejecting the use of force and offering “to support an inclusive reconciliation process.”

The Obama administration and its allies owe Libya such aid. Having backed the rebel movement that overthrew Mr. Gaddafi, they helped bring Libya to this point by failing to help secure the country during the past three years. Only now are the Western allies backing a relatively small-scale training program for Libyan security forces — and that initiative may be overtaken. How the Obama administration allowed Libya to descend into chaos would be a worthy subject of congressional investigation, if only Republicans could tear themselves away from bogus conspiracy theories about Benghazi.