When the results of Zimbabwe’s elections come in, Britain will have a chance to help the shattered country more actively than it has done so far – and it will have no excuse for not doing so.

If, by some scarcely believable feat, the opposition party has managed – for all the intimidation and vote-rigging – to prise President Mugabe from his 28-year rule, then Britain will be able to pour in millions of pounds of aid. That decision is easy.

But if Mugabe has clung on by rigging the vote, despite reports that the opposition had won by a long way, then it will be time for Britain to speak up much more noisily than it has done, shaking off the inhibitions that it has felt perhaps too keenly because of its colonial past.

Britain has chosen to keep quieter than it might have done as Mugabe took Zimbabwe from stability and prosperity into poverty and violence, with the lowest life expectancy in the world and one of the highest rates of Aids infection. It has been inhibited by its past role as the colonial ruler of Zimbabwe, then Rhodesia, until 1980, and Mugabe’s success since then in portraying Britain as the would-be oppressor. When Britain criticised him, he could use the “evidence” of British colonialism to stir up his supporters at home, and to rally other African leaders to his cause.

Tom Porteous, the UK director of Human Rights Watch, the research and lobby group, argues that Britain “made the right decision, for once” in not being more confrontational, because it would have been counter-productive. He added that Human Rights Watch was “all for people speaking out about human rights abuses. But Britain made its position [on Mugabe] very clear, and it’s also clear that when it did raise its voice, that was presented as a colonial voice by Mugabe.”

Raising Britain’s voice, in this case, might mean trying to drum up support against Mugabe in the United Nations, and shutting the British High Commission in Zimbabwe. But Britain has wanted to keep a lower profile partly, officials say, to protect those with British connections living in Zimbabwe. The careful line of the Foreign and Commonwealth Office has been that it supports “effective and well-managed land reform”, although Mugabe’s compulsory seizure of white-owned farms has taken the country into violence and near-starvation, as the output from the farms of this once hugely productive country collapsed.

Instead, Britain has tried to work quietly through the United Nations, and has lobbied South Africa in a near-futile bid to persuade President Mbeki to put pressure on Mugabe. Yesterday Gordon Brown telephoned Kofi Annan, the former UN Secretary-General, and Mbeki.

For all the careful restraint of this policy down the years, there must be a sense that Britain could have done more at least in expressing its outrage in the past few years as Zimbabwe’s economic crisis accelerated. There surely comes a time when the disaster is so huge and so inescapable that it punctures the claims that any criticism is merely a ghostly echo of the spirit of 30 years ago.

These elections are surely that turning point. Even Mugabe’s supporters – even Mbeki – have to acknowledge the straits the country is in. If there are signs that Mugabe has rigged the election result, then no sense of colonial past should inhibit Britain from calling loudly for other countries to club together against him.

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