Soresore - a huge pile of irrelevancy and no train of thought from you (as usual).

The USA and the UK (etc) have no right to interfere in internal Afghani matters as such. It's a shame, but that's the state of play.

They do have a right to defend themselves against aggressors within Afghanistan targetting targets outside Afghanistan.

In pursuing that right they do not have the right to devastate the country or kill its people (other than such aggressors).

None of which addresses the OP's point - can the USA (and UK) get out without (a) getting massacred in the process or (b) leaving things worse than before or so that they will get worse than before?