Sixty days is too short. But it still might be enough if the two sides — and the Americans — use the time to negotiate the borders of the new Palestinian state. (Those maps, give or take a little, were drawn up years ago.) Once borders are set, Palestinians could have more confidence that their long-promised state will become a reality. Israelis would know which settlements will become part of Israel in the land swaps that must be part of any agreement and could then resume building there.