It will be days before a reliable estimate of the number of people killed or injured by the massive earthquake that leveled most of Haiti's capital city of Port au Prince can be made. But the death toll will be high. The city consisted of perhaps 3 million mostly impoverished people crammed into concrete buildings. Some Haitian officials fear the dead may number in the hundreds of thousands. Bodies are being lined up along the city's streets.

Haiti was a disaster before the earthquake struck. Its people are the most impoverished in the western hemisphere. The average per capita income is less than $5 per day. The afflictions attendant to poverty infect most Haitians; 80 percent are poor and one-fifth of the population lives in abject poverty. Haitians have the highest birthrate in the West, a fact that compounds their problems.

Nearly half of Haiti's population is illiterate. They faced a high risk of infection with typhoid fever, hepatitis, diarrhea, malaria and dengue fever before the quake. Now, with water supplies contaminated and the city's sewer system useless, that risk moves toward certainty.

Once the immediate needs of the 3 million Haitians whose lives have been upended by the quake are addressed, the world's developed nations will have to decide what to do about Haiti in the long term. More earthquakes are a possibility. More hurricanes a certainty. A life of wretched poverty is also in store for most Haitians unless the island can recover environmentally, control its people's birthrate and develop an economy capable of feeding its citizens.

Aid is en route to Haiti from all over the world. President Obama has promised America's "unwavering support." To rebuild the destroyed city, that support will have to be large and ongoing. Tuesday's earthquake is only the latest in a string of natural disasters to hit Haiti. In 2008 four hurricanes blasted the island, and many residents lost what little they had.

People can help in a host of ways. The CNN television network is among the entities providing a list of reputable charities providing aid and sending volunteers to Haiti. They include the American Red Cross, Doctors Without Borders, the International Committee of the Red Cross, Catholic Relief Services and UNICEF USA.

The effort to save Haiti should be led by the United States and by France, the nation that colonized Haiti and left it with a damaged ecosystem and no good way to support itself.

In his book Collapse, author and scientist Jared Diamond compares the fates of Haiti and the Dominican Republic, the former Spanish colony that occupies the larger half of the island of Hispanola. The landscape was kind to the Dominican Republic. The mountains that separate that nation from Haiti send most of the rain its way where it falls on large spans of flat, fertile land. Agriculture flourishes. Haiti's soils are drier and poorer and its terrain far more mountainous. In Port au Prince, homes clung to hillsides deforested by the French for timber and stripped of trees by Haitians for fuel.

France developed a plantation economy based on slavery in Haiti. Spain did not do so on its part of the island, so while a functioning export economy took longer to develop in the Dominican Republic, one exists. The nation's 2008 per capita income of $8,672 is five times that of Haiti. It is a prime destination for tourists. Haiti was a failed state before the earthquake. Its people needed the world's help to survive.

Now they need it more than ever.