The US deployed approximately 1,500 additional troops to Hamid Karzai International Airport in Kabul to regain and retain security and control as the State Department and Defense Department frantically attempt to evacuate the remaining Americans, third-country allies, and Special Immigrant Visa (SIV) Afghans following the total collapse of the Afghan government in the face of a massive Taliban offensive. The current total number of US troops on the ground in Kabul is approximately 4,000.
The new troops were likely the extra infantry battalion that had been recently deployed to Kuwait as a staged quick reaction force (QRF) in support of the evacuation effort. In a DOD press release MG Taylor also stated additional "equipment" was flown in.
Chaotic footage showed US troops attempting to disperse crowds away from military aircraft and runways. Later-filmed witness footage appears to show the crowds separated from the military side of the airfield and US troops standing shoulder-to-shoulder to ensure it stays that way.
MG Taylor went on to estimate that they will be able to depart one flight an hour and evacuate 5,000-9,000 passengers a day, but given the nature of the situation, any number of factors could influence actual evacuation rates.
In the same press release, Garry Reid, Director for Defense
Intelligence (Security and Intelligence) stated that the US is currently looking to take in 20,000-22,000 Afghan refugees and temporarily house them at military bases in Texas and Wisconsin.