This page has never been shy about criticizing Prime Minister Ariel Sharon. But this week the last Jewish settlers left Gaza, completing Israel's withdrawal from the desert it took control of 38 years ago. And yesterday, Israeli soldiers completed the evacuation of four much smaller settlements among the hundreds on the West Bank. This is the first time Israel has abandoned communities in lands the Palestinians claim for their future state, so it is incumbent upon us - and all of Mr. Sharon's many critics - to reflect on this extraordinary accomplishment.