US diplomats in Kabul wrote a memo last month warning Secretary of State Antony Blinken that Afghanistan’s government could quickly collapse — appearing to contradict President Biden’s contention that the US government was surprised by the swift Taliban takeover. Nearly two dozen diplomats signed the July 13 memo urging the State Department to start processing vulnerable Afghans for visas to the US and to begin evacuations by Aug. 1, well before they gained momentum. The memo, signed by 23 embassy staffers, was submitted through the State Department’s Dissent Channel, a rarely utilized forum through which foreign service officers are able to raise internal concerns about US policy. One day after the memo was submitted, the Biden administration launched Operation Allies Refuge to orchestrate the departure of Afghan citizens who assisted the US military. But evacuation flights didn’t accelerate until last week when the Taliban had already seized major Afghan cities and neared Kabul. “Without going into detail, the dissent cable called for us to begin an airlift operation, which was announced the day after the cable was received,” a source familiar with the memo said.