Less than 24 hours before Ugandan president Yoweri Museveni began deploying the vanguard of a peace mission to Somalia, his police force was busy firing tear gas to disperse demonstrators in central Kampala.

The protesters accused him of presiding over a breakdown in the rule of law after security agents re-arrested six treason suspects released by the High Court and beat a lawyer unconscious, the latest sign of growing autocracy that has dismayed international donors.

But when the first Ugandan troops trotted down the cargo ramp of an aircraft at Mogadishu International Airport the next day, Mr Museveni took a clear step towards strengthening relations with his most important ally - the US.

"Public perception is against him; people increasingly see him as hardline and intolerant," said Angelo Izama, of the Daily Monitor newspaper. "But the opposition knows he's got a powerful ally in his camp."

Once feted as a soldier-scholar who overthrew a corrupt regime to introduce a measure of free market prosperity, Mr Museveni lost support at home and abroad when he broke a promise to step down after parliament changed the constitution to allow him to run again.

A year after the elections, he has reinvigorated his leading role in the US "war on terror" by dispatching the first contingent of a planned 1,600-strong Ugandan mission to Mogadishu - a city that has a history of sending well-meaning foreign troops home in body bags.

A volley of mortar rounds landed near the airport as the first 400 troops arrived on Tuesday, while nine civilians were killed and two Ugandan soldiers wounded the next day when rockets were fired at a Ugandan convoy driving through Mogadishu. But for Mr Museveni, the risk to his troops may be a price worth paying.

Like Meles Zenawi, Ethiopia's prime minister, who enjoys US support as a counter-terrorism ally in spite of a crackdown after elections in 2005, Mr Museveni's strategic role has encouraged Washington to damp criticism of him.

Forged during the Clinton years when Mr Museveni formed the linchpin in a regional alliance against the Islamist government in Sudan, his long-standing convergence with US security interests has again come to the fore in Somalia.

The deployment of Ugandan troops under the banner of the African Union in Mogadishu is key to the US strategy to deny suspected al-Qaeda agents a base in a country they fear could be used as a staging post for attacks in east Africa.

The US gave its tacit blessing when Ethiopia invaded Somalia in December to overthrow a coalition of Islamists accused of links to al-Qaeda. Washington is counting on the Ugandan-led force to protect a weak interim government as Ethiopia withdraws.

At a news conference alongside a visiting US general last week, Mr Museveni stressed he was sending troops to improve regional security rather than to act as "policeman" for the US, although he acknowledged Washington was providing funding.

"We have the courage," he said, "but we do not have the money."

Already under fire, the Ugandans are looking rather lonely. The AU is hoping to muster 2,500 more troops from Ghana, Malawi, Bur-undi and Nigeria, but UN officials say 8,000 are needed.

One diplomat in Kampala described the deployment as a "suicide mission", but Mr Museveni displays unblinking faith in an army he built from a tiny band of comrades who launched his guerrilla war against former president Milton Obote in 1981.

Given the scandals in Uganda, some Ugandans argue the troops would be better off staying at home.

Sources:FT