MOMBASA, KENYA – Nearly seventy years ago, German U-boat submarines sank millions of tons of

Allied shipping, killing tens of thousands of sailors and threatening Great Britain with ruin. The key to defeating U-boats was cooperation: cargo ships and warships would clump together for mutual protection. The resulting convoys turned the tide against the German underwater menace and helped win the war for the Allies.

Today convoys are making a comeback, as a tactic for deterring pirates operating along the Somali coast. Several times a month, chartered cargo vessels link up with warships for the dangerous dash into the

Somali ports of Mogadishu and Merka. During World War II, convoys sailing from the U.S. to Great Britain carried everything from weapons to food to fuel. But today's convoys are hauling just one thing: donated food, enough to feed half a nation.

Here in Mombasa, in southern Kenya, the U.N. World Food

Program runs one of the world's biggest humanitarian campaigns, sending up to

50,000 tons of food per month into Somalia to feed 40 percent of the country's

8 million people, according to WFP spokesman Peter Smerdon. Food aid for

Somalia isn't new: the country's been on the dole since the ruinous civil war of the early 1990s. But demand for aid has steadily increased, jumping some 75

percent this year. Due to the threat of bandits on Somalia's remote, dusty roads, most of the food comes by sea.

But it didn't take long for Somalis to figure out that you can stake out a sea lane just like you can a road. In the '90s, pirates began seizing food ships. At first, the pirates claimed they were just trying to make sure the food got distributed fairly: warlords on land had been grabbing entire food shipments straight out of the U.N.'s hands. "Pirates said, 'We shall seize the vessels so everyone gets the food,'" recalls Frederick Wahutu, a longtime sea captain who now directs the Kenya Ships Agents Association in

Mombasa. Whether legit or not, this supposed altruism backfired, when crews refused to sail into Somali ports as long as ships remained vulnerable to pirates. Suddenly nobody was getting any food.

The U.N. issued a desperate plea for warships to escort food convoys through pirate waters, and the whole world responded. In recent years, several navies have unilaterally donated warships, including the Dutch and Canadians. This fall, a NATO force led by a Greek frigate took over the escort mission. And this week, the European Union relieved NATO with ships from the U.K., France and Germany. It's the first-ever E.U. naval deployment, coming hot on the heels of the E.U.'s first overseas land deployment to Chad, this spring.

This weekend the first E.U.-escorted convoy will sail from

Mombasa, with a French or British frigate providing the heavy firepower.

"With escorts, we're getting more food in," Smerdon said. But don't expect the same tactic to work for commercial ships plying the Gulf of Aden. According to Wahutu, most commercial ships sail on strict schedules. "If you have to wait for a convoy to form up, you lose time." And time means money.

So while the world's biggest food campaign piggybacks on

World War II-style convoys, for-profit shipping is still going it alone, despite the risks.