The second anniversary last week of the devastating Haiti earthquake, which killed around 150,000 people and destroyed much of Port-au-Prince, brought reports of mixed progress. About half of the rubble has been cleared (if that sounds slow, consider it took five years to remove far less rubble in Aceh after the 2004 Indian Ocean tsunami). About half a million people are still living in camps in Haiti — but that is down from closer to 1.5 million two years ago. Meanwhile cholera, introduced by U.N. peacekeeping troops, killed over 7,000 people in the aftermath of the crisis — the infection rate has abated but the disease remains endemic.

Progress after a disaster is always slower than hoped. For all the benefits that the donor community has provided in reconstruction, one reason for the lack of progress is the often snail-like pace of heavily bureaucratized assistance efforts in the chaotic post-catastrophe conditions of weakly governed states. For example, only about half of the cash promised by donors to Haiti for 2010-2011 had been disbursed by last month, and the figure for U.S.-given aid is only about 30 percent. There is still a huge gap between donor disbursement and impact on the ground; a lot of the resources have been disbursed only as far as implementing agencies like NGOs and international agencies, many of whom have yet to spend the cash.

Finally, even when implementing agencies do finally spend that money, much of it will go to pay foreign contractors rather than local people. According to analysis by the Associated Press, Haitian firms successfully won only 1.6 percent of the value of U.S.-funded disaster recovery contracts issued in 2010. Yes, local firms were subcontractors on many of these contracts, but a large proportion of U.S. funding disbursed to support Haitian reconstruction ended up in the U.S. bank accounts of development contractors. We need more rapid ways to get relief directly to disaster victims, including the hundreds of thousands still suffering in the aftermath of the Haiti quake.

Luckily, we already have one: migration. Immediately after the quake, about 200,000 Haitians living in the United States without proper documents were granted “temporary protected status,” which allowed them to work — and send money home — without fear of deportation. That single step may be the greatest contribution America has made towards Haiti’s reconstruction to date. That’s because the 535,000 Haitian migrants in the United States send home remittances worth as much as $2 billion a year. An early estimate by World Bank economist Dilip Ratha suggested that the temporary protected designation might have been worth as much as $360 million in additional remittances to Haiti in 2010 alone that’s more than total U.S. aid disbursements to the country in 2010 and 2011.

Beyond being a powerful short-term recovery tool, migration is vital to the long-term development of Haiti as well. Economist Michael Clemens, my colleague at the Center for Global Development, suggests that four out of five Haitians who have escaped destitution have done so by leaving the country. Meanwhile, the potential benefit of a diaspora for Haiti’s future prospects have been repeatedly demonstrated: one need only look at Indians working in Silicon Valley who were key to creating Bangalore’s booming IT industry or Africans spending time abroad who are responsible for creating new export industries back home. Across countries, larger migrant populations lead to greater trade, investment, and learning.