Mugabe Soldiers on

The latest spasm of violent repression in Zimbabwe has sparked speculation that the era of Robert Mugabe may finally be drawing to a close. But the country's self-styled founding father and president since 1980 shows no sign of leaving voluntarily - and it remains unclear who or what can force him out.

Rather than loosening Mr Mugabe's grip on power, factional rivalries within the once monolithic ruling Zanu-PF party have enabled him, so far at least, to divide and neutralise his critics. Disaffection within the army and police over the impact of inflation on wages and prices has encouraged absenteeism and desertion but, as yet, no overt mutiny.

The regime's willingness to use brute force, seen again in Sunday's beating and torture of opposition leader Morgan Tsvangirai and others, has proven effective until now in discouraging large-scale political protests. The flight into exile of up to 3 million Zimbabweans - almost a quarter of the population - has weakened opposition on the ground.

Additional factors are contributing to Mr Mugabe's presidential longevity. The regime has systematically, although not wholly successfully, intimidated the judiciary while media controls and censorship mean egregious official incompetence and corruption often go unreported.

Most importantly of all, perhaps, ineffective, sporadic engagement by the international community has also enabled Mr Mugabe to thumb his nose at foreign critics. Former colonial power Britain, the EU, and the Commonwealth have all shown themselves powerless to promote change using limited sanctions and official ostracism. So, too, for mistaken reasons of regional and racial solidarity, as well as sheer inertia, have South Africa, Zimbabwe's influential neighbour, and the Southern African Development Community.

And while Bush administration officials occasionally talk about Zimbabwe as a rogue state and a threat to international peace and security, there is no thought of active, Middle East-style intervention there.

Mr Mugabe, meanwhile, fresh from celebrating his 83rd birthday last month when he was hailed by state-controlled media as "an unparalleled visionary" and "an international hero among the oppressed", is manoeuvring to extend his incumbency to 2010 or even 2014.

"The party is so divided, it's difficult to see who could remove the old man," said Richard Dowden, director of the Royal African Society. "I don't think things have changed so dramatically that you can talk about the government being toppled. Mugabe is a master manipulator and he's still on top of things."

All the same, Mr Mugabe's position is far from secure. The weekend's shocking violence may galvanise rather than deter the protesters, accelerating the consolidation of a united opposition under the Save Zimbabwe Campaign umbrella. Zimbabwe's prolonged economic and institutional decline may also be finally approaching a tipping point, rendering the country ungovernable.

And if the regime's brutality increases as it struggles to keep hold, the neighbours - and the west - may finally be embarrassed into decisive action.

Yet even if Mr Mugabe goes, radical political and economic reform, including a power-sharing transitional government and a new constitution, will still be urgently required, an International Crisis Group report concluded this month. "A deal that merely removed Mugabe while in effect maintaining the political status quo by keeping Zanu-PF in power would be no change at all."