HUMANITARIAN crises are seldom just humanitarian: Almost always, the malnutrition and the misery have political causes. The brutal wars in Sudan and Congo account for those countries' appalling civilian death tolls. Political repression explains the hunger in North Korea and Zimbabwe. Even the HIV pandemic reflects the failure of politicians to challenge gender inequality and sexual taboos.

Niger's food crisis has its own political dimension. The government has been criticized for playing down the crisis -- it speaks of a food shortage rather than a famine -- and for resisting calls to distribute free food. International financial institutions, which urged a value-added tax on food and imposed budget controls that discouraged the government from maintaining emergency food stocks, also deserve some of the blame. Even so, Niger's crisis is less political than many. This landlocked country of about 11 million is a democracy. There is no war going on there. Some 2.5 million people need emergency assistance because of natural disasters more than politics: a swarm of locusts that ate much of the millet harvest, followed by a drought.

Usually, natural disasters attract a generous response. The tsunami last Christmas was a prime example, and earthquakes and hurricanes generally prompt individuals and their governments to open their wallets -- or at least to pledge generously, even if they don't always deliver. But Niger has not even been that fortunate. As early as last November, the government and the U.N. World Food Program appealed for emergency food aid and money; only Luxembourg responded. The United Nations followed up with a second appeal in March and a third in May. Only recently has the money begun to come.

If Niger's largely unpolitical emergency cannot trigger prompt sympathy, it's time to rethink the way relief is organized. The world depends on an ad hoc, pass-the-hat system; there's no standing ability to respond quickly when the first signs of disaster appear. This raises the cost of action. In the Sudanese province of Darfur last year, donors didn't provide enough relief before the onset of the rainy season, so part of their belated assistance had to be airlifted into the region at enormous expense. Similarly in Niger, the United Nations estimates that saving a life would have cost a dollar of aid back in November but may cost $80 or more now.

To avoid this waste of cash and lives, U.N. Secretary General Kofi Annan has proposed an emergency fund of $500 million from which to finance rapid response to future famines. In the wake of the oil-for-food scandal, the onus is on the United Nations to show that it can manage that sort of money without corruption; perhaps it cannot. But whichever institutional home one favors for it, the idea of a global famine fund makes sense.