Zimbabwe's political power-sharing deal – the hope of that tattered country – is on the verge of collapse. Big-man leader Robert Mugabe has grabbed the mightiest ministries for himself, handing paltry leftovers to the opposition. But the problem is not that Mr. Mugabe won't share. It's that his top generals fear what will happen to them if he does.

The fear is typical of perpetrators of violence and suppression whose influence is coming to an end. In Africa, it gripped military and political leaders in Rwanda, Burundi, and Liberia, to name a few countries once cleaved by civil war and atrocities.

It didn't come to civil war in Zimbabwe, which not long ago was a prosperous nation, and now suffers searing inflation, joblessness, and hunger. But its citizens well remember the burned homes, beatings, rapes, and killings by President Mugabe's security forces in the run-up to last June's presidential election.

Had the campaign been fair and safe, Morgan Tsvangirai, the leader of the opposition party Movement for Democratic Change (MDC), would have likely ousted Mugabe, who has ruled for 28 years. Instead, Mr. Tsvangirai signed a deal last month that allows his nemesis to stay on as president, while he takes the post of prime minister. Cabinet ministries are to be almost evenly divided between Mugabe's ZANU-PF party and his rivals.

At the signing, though, it wasn't decided who would get which ministries, and negotiations have broken down. Tsvangirai indicated he could live with the Army in Mugabe's portfolio, if he could have the police (which brutalized him and many MDC faithful) and also the finance ministry, which must change hands if the West is to gain confidence in a new unity government and lift sanctions.

But this sensible allotment has met stiff resistance in Mugabe's camp. Part of the concern is loss of patronage. The far more serious obstacle is the worry by the military brass that they will be investigated by police who come under Tsvangirai's control – and then prosecuted.

Tsvangirai has publicly said he has no interest in retribution, but the power-sharing deal does not guarantee immunity, and the generals remain suspicious. They sought protection in Mugabe, who owes them his job, and he obliged last week by unilaterally claiming the police and key ministries.

When African leaders meet in Zimbabwe Oct. 27 to try to end this impasse, Tsvangirai wants them to pressure Mugabe. But the pressure seems misplaced. It is the generals who need persuading.

In the near term, Tsvangirai should build bridges to the military leaders and try to establish some level of trust. This is how, for instance, Burundi has been able to move forward since signing a peace accord in 2000 (an accord that also did not guarantee immunity).

In the longer term, Zimbabwe needs to find a balance between justice and mercy. It has a model in South Africa's Truth and Reconciliation Commission, which investigated apartheid's human rights violations, sought reparation for victims, and weighed amnesty.

If Zimbabwe is to unify and heal, it must move from big-man to big-heart politics. That's a long journey, but if Tsvangirai begins by taking the first step, he makes it easier for Mugabe & Co. to follow.