We evacuated around 330,000 Britishand allied personnel off the beaches of Dunkirk yet it was still a military disaster and some effort was made to destroy at least some of the equipment left behind in France
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The important thing now is that those Americans and other foreign nationals still in Afghanistan who do still need to get out find a way of doing so. One can't expect the White House to publicly explain their plans to evacuate the remaining Americans before any such plans have been executed because, presumably, the Taliban listen to the news.
I still believe that the "West" will have to go back into Afghanistan at some point in the future, like it or not.