IT will take a while, but the long and brutal reign of Robert Mugabe in Zimbabwe is probably nearing its end. It is not because of the democratic opposition at home, whose members are regularly beaten up and sometimes killed by the police. Not even because neighbouring countries in southern Africa are at last putting pressure on Mugabe to go. It is just because his own partners-in-crime have decided that it is him or them.The key moment actually came last December, when for the first time the senior ranks of the ruling Zanu-PF Party stood up to Mugabe and refused to accept his proposal to postpone the next presidential election from 2008 to 2010. It was typical Mugabe salami tactics - give me two more years and maybe I will decide to resign in 2010, but this time it did not work. "In that case," said Mugabe, "I'll run for president again in 2008." (which would keep him in the presidency for his 90th birthday in 2014). Given the speed with which Zimbabwe's economy is collapsing and its population fleeing abroad, seven more years of Mugabe and it will not be worth inheriting power there. So Mugabe's potential heirs within Zanu-PF itself have begun to rebel.