BAGHDAD, Nov. 7 — American forces have routed Al Qaeda in Mesopotamia, the Iraqi militant network, from every neighborhood of Baghdad, a top American general said today, allowing American troops involved in the “surge” to depart as planned.

Maj. Gen. Joseph F. Fil Jr., commander of United States forces in Baghdad, also said that American troops had yet to clear some 13 percent of the city, including Sadr City and several other areas controlled by Shiite militias. But, he said, “there’s just no question” that violence had declined since a spike in June.

“Murder victims are down 80 percent from where they were at the peak,” and attacks involving improvised bombs are down 70 percent, he said.

General Fil attributed the decline to improvements in the Iraqi security forces, a cease-fire ordered by the Shiite cleric Moktada al-Sadr, the disruption of financing for insurgents, and, most significant, Iraqis’ rejection of “the rule of the gun.”