DOLO, Somalia — Is the world about to watch 750,000 Somalis starve to death? The United Nations’ warnings could not be clearer. A drought-induced famine is steadily creeping across Somalia and tens of thousands of people have already died. The Islamist militant group the Shabab is blocking most aid agencies from accessing the areas it controls, and in the next few months three-quarters of a million people could run out of food, United Nations officials say.

Soon, the rains will start pounding down, but before any crops will grow, disease will bloom. Malaria, cholera, typhoid and measles will sweep through immune-suppressed populations, aid agencies say, killing countless malnourished people.

In a way, this is all déjà vu. In the early 1990s, Somalia was hit by famine, precipitated by drought and similarly callous thugs blocking food aid and producing similarly appalling images of skeletal children dying in the sand. In fact, the famine back then was in the same area of Somalia, the lower third, home to powerless minority clans that often bear the brunt of this country’s chronic troubles.

But in the 1990s, the world was more willing to intervene. The United Nations rallied behind more than 25,000 American troops, who embarked on a multibillion-dollar mission to beat back the gunmen long enough to get food into the mouths of starving people.