Sort of surprised this didn't come up. France, with good reason, is also questioning the U.S. role in Haiti.
Both the U.S. and France have controlled Haiti in the past. Haiti's economic turmoil is in no small part due to France's demands that Haiti pay them reparations for their freedom and that the U.S. made them pay a 40 million dollar loan for occupying their country for 19 years. Haiti has been denied debt cancellation up until last september. The U.S. is also responsible for causing a war between Haiti and the Dominican Republic. In the 1970s and 80s the U.S. supported the oppressive Duvalier regime, in no small part because Haiti was allowing U.S. manufacturers to establish plants on the island. In 86 the U.S arranged for the Duvalier to seek refuge from protests in France. The U.S. has intervened in Haiti in 1888, 1915, 1994, and in 2004 was described by the president Haiti as "kidnapping" him and sending him to C.A.R. Since 2004, the U.N. has had a presence in Haiti. Both Venezuela and Cuba recently renewed their alliances with Haiti in 2006 and 2007.
The point of me repeating these Wikipedia facts is that it would seem to be denying reality to say the U.S. has not demonstrated time and time again to have an invested interest in the island - not just a benevolent, "hope you are doing well," interest either. It has placed banks in Haiti under U.S Banking control, has establish manufacturing plants, and obviously Haiti holds a geopolitical importance in that the U.S. does not want to see even more countries in the Americas begin to be ruled by leftist, populist rulers like Chavez and Morales. And, look, not to be condescending but if you haven't noticed this trend in American foreign policy in the Americas you must be willfully not recognizing it. We want these countries for our companies and to support us in our adventures abroad. We do not care what their leaders do to their people as long as they don't galvanize them into an Anti-American movement. This compounded with Naomi Klein's hard to deny "Shock Doctrine" and Rahm Emanuel's "Don't let a good crisis go to waste," it is easy to connect the dots. American aid almost always comes with strings attached, that is how we have hundreds of military bases on nearly every continent in the world. http://www.militarybudget.info/overseas.html
But earthquake machines? Not so much.