Quick and brutal. The Taliban are in Kabul already. US intelligence said 90 days. Which shows how accurate their understanding of Afghanistan is, and that is the level of intelligence which they used to attempt nation building.

The US is supposed to have asked the Taliban leadership to remain outside the city until they evacuated. That doesn't look like it's going to happen. Local Talib commanders never listen to their leadership anyway, and different commanders may be racing to capture resources and influence.

The US have now put the Taliban in the position where they can be seen to stand by and "allow" the most powerful country in the world to evacuate safely with its tail between its legs. Followed by lap-dogs like the UK.

Afghans already think the world has abandoned them. Because it has.

If the Taliban control airport road, they then may detain Afghan nationals and prevent them leaving. The US will probably secure the corridor between the Embassy and KIA. But, unless concerned US citizens make a might storm of complaint and political action about it, it looks like they will abandon their Afghan national employees. Unfortunately, I see no sign of such political activity. It needs a bit campaign.

The Mayor of Kabul will become the Mayor of only Kabul Airport, presumably, which the US will make safe until its nationals are transferred from the Embassy and out. Turkey was tasked to defend the airport. They've just announced that they will evacuate just as their role becomes crucial. Is there time for a handover to the US and UK…