China and Russia seldom do the right thing at the United Nations, but on Friday they vetoed an economic war on Zimbabwe. They are also balking a similar war on Iran. Whatever their motives, they are right. Sanctions are an ineffective, or worse a counterproductive, weapon of interstate aggression.

The foreign secretary, David Miliband, yesterday called the veto a “severe blow . . . to timely and decisive security council action”. Sanctions are never timely or decisive. They are a political demonstration. While the decision will be greeted with glee by Robert Mugabe, Britain’s UN ambassador, John Sawers, should never have proposed them as offering the Zimbabwean people “an end in sight to their miseries”. They offer no such thing.

Unlike war, which is violence aimed at conquering and replacing a regime, merely engineering a shift in terms of trade is play-acting. As a gesture of soft power, sanctions were first imposed on Italy during the Abyssinian crisis of 1935 and did not work. Yet their appeal is undiminished. Macho in rhetoric yet painless to the imposing nation, they replace guns and bombs with trade returns and computers.

History offers one generalisation: that sanctions add longevity to anyone on whom the West imposes them.The most sanctioned leaders of the past half-century have been Fidel Castro, Colonel Gadaffi, Saddam Hussein, Aya-tollah Khomeini, the Taliban, the Burmese generals and the rulers of North Korea. None was brought down by them. Where intervention was effective, as in the Falklands, Haiti, Afghanistan, Serbia and Iraq, it required force.

Nothing is more arrogant than a powerful nation’s belief in the efficacy of all it does. If a sanction is imposed and does not achieve its goal, it was not tough enough. If the goal does occur, then its sanctions must have been the cause. Such is the West’s omnipotence that lesser states must always be dancing to its tune. Whenever there is trouble in the world, said Kipling, “An’ then comes up the Regiment an’ pokes the ’eathen out” – even if the regiment is nowadays a trade regulator.

Students of sanctions remain mystified by their appeal. They are near impossible to make leak-proof and just establish more costly and corrupt conduits of trade. Kofi Annan of the UN calls them a “blunt and even counterproductive instrument”.

The most detailed examination, by Richard Haass of the Brookings Institution for Congress in 1999, concluded that they were so blunt as “often to produce unintentional and undesirable consequences”, such as strengthening the regime they were supposed to be undermining. Free trade economies are by their nature open and thus susceptible to pressure. Besieged ones are authoritarian and closed against pressure.

This has not stopped South Africa being constantly cited as a prize exhibit of the sanctions lobby. Through the 1980s that country experienced comprehensive (although not leak-proof) embargoes on trade and finance. This was indeed followed by regime change, albeit some 10 years later. Those involved in impos-omy. Financial sanctions and, later, disinvestment complicated credit lines, but the central bank behaved responsibly in controlling money supply, unlike Zimbabwe’s. Ownership of foreign food, retail and car manufacturing shifted into Afrikaner hands. Profit was no longer exported to America and Europe.

Studying sanctions at the time, I concluded that they helped to prolong the white regime by as much as a decade, shifting power from more liberal to less liberal groups. Sanctions did not weaken the regime.

Ostracism hurt the pockets and the pride of many cosmopolitan South Africans – the sort westerners meet – but they did not hurt half as much as socialism hurt the rest of Africa. South Africa under sanctions was not poor in African terms. Its leaders decided in 1989-90 to transfer power peacefully to blacks, largely because they thought it was safe to do so. A body of white opinion found apartheid intellectually and morally unsupportable.

In so far as South Africa felt under pressure it was not economic but military. As long as Nel-son Mandela was in prison he was a catalyst for terrorism, as was the presence of hostile regimes along the northern border. Sanctions “worked” only for those outside the country, such as America’s Jesse Jackson, determined to cast themselves as agents and heroes of change. They were as patronising as they were wrong.

Sanctions may not make a country wealthy in the longer term, but they can make a regime more secure in the short one. They also enrich its ruling elite. Sanctions made Saddam the sixth richest man in the world and Serbia’s Milosevic the king of a mafia organisation. They are pouring money into the pockets of the cronies of Mugabe, Mahmoud Ahma-dinejad and the Burmese generals.

The recent drift from general sanctions into “smart” ones is a measure of their futility. But smart sanctions are no less absurd. In South Africa the exclusion from Test matches did not lead Afrikaners to vote for progressive MPs. The idea that Mugabe might decide to stand down because his wife cannot shop at Harrods is like imagining the Iranian mullahs crying over their exclusion from the Rue St-Honoré.

The threat of economic siege drives a nation towards state power, as does the threat of terrorism in the West. It makes governments behave more not less repressively and the populace become more not less dependent on it. The middle-class customary reservoir of opposition to dictatorship is debilitated and driven into exile, as happened in Iran and Iraq.

That impoverishing the poor and inconven-iencing the rich somehow leads to bloody revolution must be the most brainless concept ever to pollute international relations. People rarely rise up and topple governments and if they do it is at the point of a gun, usually their own. Violence works. Economics does not.

The appeal of sanctions is that they are a quick answer to public opinion demanding that “something must be done”, something that does not mean body bags. They are war by other means, bloodcurdling but not bloodthirsty. But they are cowards’ war because those they hurt, usually the poor, are also defenceless. Zimbabwe’s sanctions are inducing its regime to ensure that only its supporters have food. That may make our Foreign Office feel better but what good does it do?

The last desperate cry of the sanctions lobby is: if not sanctions, what? It is as if any gesture were better than none. The truth is that if you want to overthrow a regime you should do it, as the Victorians did. If not, stop pretending.

In 1925, after the great war, the international community outlawed chemical weapons as repellent even in total war. The agreement was remarkably successful, at least until Saddam’s day. So too was a similar revulsion against nuclear weapons after Hiroshima. There is honour even among warmongers.

Perhaps one day economic sanctions, a weapon of international conflict that uniquely attacks civilians, might also be removed from the arsenal.

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