We don't need guns to help the people pitch Mugabe from his perch

Whether you believe in him or not, it's time to give God a helping hand. Robert Mugabe, the Catholic mission school boy turned tyrant, says "only God" can remove him from power in Zimbabwe. In that case, I'm rooting for God. Go for it, Lord. (Silence on high. Damn.)

What we see in Zimbabwe today is naked political terror, orchestrated solely to extend the reign of a once legitimate but now illegitimate ruler who has led his people to a hell on earth. Destitution, murder, rape and mass beatings are the order of the day, and a so-called election this Friday which is now the barest sham. Let Mugabe himself be my witness. "We are not going to give up our country because of a mere X," he warned earlier this month, according to a report by Chris McGreal in Tuesday's Guardian. "How can a ballpoint pen fight with a gun?" Mugabe asked.

If "only God" can remove him, Mugabe also says, "the British and Americans want to play God. They have given themselves a role which is not their own, of installing and deposing governments. They want to do the same here but we say to them they are not God."

Especially in the post-colonial south, and especially after Iraq, that argument has traction. When South Africa's ANC - which could make the difference in Zimbabwe in a way that London and Washington cannot - finally came out this week to condemn the Zimbabwean government for "riding roughshod over the hard-won democratic rights" of its people, it made a point of recalling how Africa's former colonial rulers trampled on the principles of freedom and human rights. "No colonial power in Africa, least of all Britain in its colony of 'Rhodesia'," it argued, "ever demonstrated any respect for these principles."

Then there is the appeal to absolute, unlimited state sovereignty. At an election rally on Tuesday, Mugabe cried: "The elections are ours; we're a sovereign state, and that is it." By contrast, the opposition leader, Morgan Tsvangirai, has called for an African-led and UN-backed team to facilitate a transition in the country. Senior people in his own party, which won more seats than Mugabe's Zanu-PF in the parliamentary elections in March, will privately go further. They do not believe that rulers should be allowed to get away with murder - literally, not metaphorically - behind an iron curtain of absolute sovereignty. They are asking for more help from outside. They want the UN to go further than it has in its recent security council resolution, and above all they want South Africa's president, Thabo Mbeki, to get off his fence. To accuse them of being western neo-colonialists is as absurd as it would be to accuse a murder victim of being a murderer.

So Zimbabwe brings us back to this great argument of our time, about the rights and wrongs of intervention. And the first thing to say is that this debate is crippled by reducing "intervention" to the single dimension of military action. There are hundreds of ways in which states and peoples intervene in the affairs of other states and peoples without resorting to the use of military force.

War, if it is to be just, must always be the last resort. In a column last month I went through some classic "just war" criteria to argue that an international military intervention in Burma was not justified. I would do the same for Zimbabwe today. For good reasons of maintaining international order, the "just cause" bar for such interventions has to be set very high - roughly speaking, at the level of actual or imminent genocide.

You would be most unlikely to get "right authority" for such action from the UN. Crucial among the objections, in the case of Zimbabwe as of Burma, is the lack of a "reasonable prospect" of success. What would these troops do and how would they make things better? The theoretical argument about legitimacy can't be divorced from the practical one about efficacy.

But the choice is not either to invade or to sit on your hands and do nothing. Either reach for the gun or leave it to the sadly silent Almighty. "Gun or God" is the Mugabe fallacy. When he asks "how can a ballpoint pen fight with a gun?" our job is to provide the answer.

Here, in no particular order, are seven things that people outside Zimbabwe can do to help the majority inside Zimbabwe have its democratic will recognised. We - through our elected governments - can work for a second UN resolution, stronger than the last. We can encourage our governments - as many as possible, especially those outside the traditional west - not to recognise as Zimbabwe's legitimate leader the president who emerges from this Friday's terror sham election (assuming it goes ahead, despite yesterday's appeal for postponement from the leaders of Tanzania, Angola and Swaziland).

We can shame the mining giant Anglo-American into not pushing ahead, under Mugabe, with its £200m investment in a platinum mine at Unki. We can spread the word that the Queen - the royal "we" - has at long last stripped Mugabe of his honorary knighthood. We can sign the petition to Thabo Mbeki and other leaders of Southern Africa on avaaz.org, to be published in newspapers across the region. (The number of signatories has risen from 90,000 to over 111,000 while I've been writing this article.)

Then anyone in London can join a planned small demonstration at Nelson Mandela's 90th birthday party in Hyde Park this Friday, respectfully asking the old hero to urge Mugabe to leave the stage. Mandela's discretion and loyalty to his successor Thabo Mbeki have, in this regard, outlived their useful term. Few contrasts are more painful than that between these two veteran anti-colonial leaders and long-term political prisoners, Mandela and Mugabe, the one ennobled and the other embittered by long struggle and imprisonment. Few voices would carry more weight in the world than that of Mandela calling for Mugabe to go.

Last but not least, we should listen to what the legitimate representatives of the majority in Zimbabwe say about stepping up sanctions. An obvious objection is: "But broader sanctions would hurt the people, who are already suffering enough." Sometimes, though, the people themselves are prepared to take the pain for long-term gain. Or at least, that's what their legitimate representatives tell us - and how else can we know? That was the message from the ANC under the apartheid regime in South Africa and from Solidarity in Poland. In both those cases, the historical record suggests that sanctions did contribute to the eventual good result. In other places, sanctions made things worse. To say simply that sanctions don't work is a useless, lazy generalisation.

On their own, none of these steps will have the desired effect. Some, taken individually, are open to easy ridicule. ("Fall, Sir Robert ..." I could write the squib myself.) And taken altogether, they won't get rid of the monster: that depends on the Zimbabweans and their southern African neighbours. But these suggestions do nail the fatalist idea that there's nothing we can do. And I'll bet you this: sooner or later, even in Zimbabwe, the ballpoint will defeat the gun.

Timothy Garton Ash