One of the funniest moments in a diary rich in funny moments is, perhaps surprisingly, about international aid. "GB popped up on the nine o'clock news," writes Alastair Campbell in the latest volume of his Downing Street Diaries, "saying he was going to write off all third world debt. Nobody," he adds, "not even TB, was aware that he was going to do it." "GB" is, of course, Gordon Brown. "TB" is, of course, his so-called boss, Tony Blair. "TB," wrote Campbell three days later, "was livid that GB, without any consultation at all, wrote off third world debt -- £155m over 10 years -- while telling us he could do nothing more for the NHS to pre-empt a winter crisis."

This was in December 1999. Eleven and a half years on, not all that much has changed. True, there's a different man at No 10. True, there's a different man at No 11. True, the man at No 11. is fairly unlikely to go on telly and cancel third world debt without telling the man at No 10. But what hasn't changed is that a British government is planning to spend big sums of taxpayers' money on foreign aid at a time (and much, much more than in 1999) when resources for British public services are scarce.

There's a famine in Africa, again. But you can't, apparently, call it a famine. You can't, apparently, call tens of thousands of people walking for days in burning heat, without any food or water, on legs so weak that they can hardly bear the weight of the skeletal body they support, with muscles so wasted that every step hurts, to a place where they might, or might not, get the food and water and shelter they need to keep alive, a famine. What's happening in Somalia, Ethiopia and Kenya, where some families have walked for over a month, and lost parents and children on the way, and where 10 million people are at risk of starvation, isn't a famine. It's a "humanitarian emergency", according to the people who decide these things, which is nearly, but not quite, but at this rate soon will be, a famine.

What caused it? The usual things. Drought. Rising food prices. War.

What can we do about it? Dip into our pockets.

Will it make any difference? Well, that depends on who you listen to.

If you listen to Dambisa Moyo, a very pretty economist from Zambia who seems to be on TV an awful lot, you'd say it won't. You'd say, as she says in her book, Dead Aid, that aid to Africa makes people more dependent, and encourages corruption, and bad government, and keeps poor people poor. (You might, of course, also say that someone who used to work for Goldman Sachs, which makes deals that make the price of things like wheat shoot up, knows quite a lot about keeping poor people poor.) If you listen to Dambisa Moyo, you'd say that aid was such a bad idea that Western countries should stop it.

If you listen to Linda Polman, a Dutch journalist who has written a book called War Games, you'd say that aid has become a very big industry that only helps the people who work in it, and people who want to wage war. You'd say, for example, that the Hutus in Rwanda stole 60 percent of the Western aid and then put a tax on food rations to pay for their militias, and that this meant the war lasted longer than it would have, and that more people than would have been otherwise were hacked to death.

You'd say that the £90 million raised by the 1985 Live Aid concerts was used by the Ethiopian regime to tempt starving villagers into camps, and that it then deported 600,000 of them, and that one in six of those who were deported died. You'd say that it might not be a brilliant idea to throw money at the country again.

If you listen to Melanie Phillips, who writes a column in the Daily Mail, and likes quoting from both these writers, you'd say that aid creates terrorist training camps where there used to be refugee camps, and that it keeps violent dictators in power. You'd say that there's not much point in giving money to Afghanistan when nearly £1 billon of international aid has gone missing. You'd say that the British give twice as much in aid as the Norwegians, and six times as much as the Germans, and seven times more than the French. You'd say that it's crazy, at a time when our own problems are getting bigger, for us all to cough up more.

And it's tempting to think that you'd be right. Quite a lot of aid is stolen by corrupt governments. Some of it does prop up horrible regimes, and some of it does prolong wars. Quite a lot of it is misused, and wasted. But quite a lot isn't. Most aid, according to Robert Cassen, who has conducted what The Economist has called "the most exhaustive study of aid ever undertaken" does, at least in terms of its own objectives, succeed.

Aid won't turn murdering thugs into Mother Theresa. It won't wipe out corruption. It won't make dictators treat their starving people well. But nor, whatever Dambisa Moyo says, will stopping it. Murdering thugs don't suddenly start feeding their own people just because nobody else will.

The answer, in as far as there is any kind of answer, is to try to do what works. If you can't establish Scandinavian-style liberal democracies in places like Somalia, who will write you nice reports and handle your money well, you have to deal with the local leaders, or the NGOs, who will keep an eye on the cash, and the work, and who will be there once the immediate crisis has gone.

Aid has become an ideological issue. The Left has been too tolerant of what doesn't work. The Right has been too mean. But there are some things that really ought to be beyond ideology. We are the luckiest people on the planet. We think corruption is MPs claiming for bath plugs, and poverty is eating at McDonald's. We're lucky to have food, and water, and shelter, and a government we elect. And we're lucky to have had a chancellor, and then prime minister, who did more for poor people in Africa than anyone else in British history, and to have a prime minister who's determined to keep the promises he made.

It's nothing less than an abomination that human beings are still dying of hunger at a time when we can send a space probe to Mars. We live with this. We will carry on living with this. We can't solve all the problems of bad people, and bad climates, and bad governments. But at least we can say that we're citizens of a country that tried.

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