A military coup in Zimbabwe may have ended — at last — the misrule of Robert Mugabe. Now the question is whether his removal can pull a once-prospering country from the ditch into which Mugabe drove it. Unfortunately, prospects don’t look good.

Mugabe was a hero of Zimbabwe’s independence struggle and took power in 1980. But he wrecked his legacy with bloody campaigns of repression. Zimbabwe’s economy nearly halved from 1998 to 2008; shortages of food and other basic goods haunt a population of about 14 million. Opposition movements have been brutally repressed, and most elections have been rigged.

That horrific record, however, was not the reason for the military coup. Rather, it was Mugabe’s recent firing of Vice President Emmerson Mnangagwa, who was vying for control of the ruling party. Mnangagwa is blamed for the killing of some 20,000 civilians in the 1980s.

Many Zimbabweans and some in Western governments may welcome any change in the country after 37 years of Mugabe. Some suggest that Mnangagwa could reverse some of the regime’s worst mistakes.

Mnangagwa is not, however, committed to an election. And without an election to provide a genuine popular mandate, the chance for reforms that could revive the economy looks small.

That’s why the U.S. and other Western governments should insist on a prompt restoration of constitutional order and a firm commitment by the military to holding internationally supervised elections next year. The outside world has leverage. The end of Mugabe’s rule offers a fragile opportunity to rescue an African country.