Tensions had been brewing throughout Europe—especially in the troubled Balkan region of southeast Europe—for years before World War I actually broke out.
I would say that President Thomas Jefferson would have desired the revolution to fail. On the one had, Saint Domingue independence from France was good news, for it debilitated the French. But on the other hand, the triumph of a slave revolution in the West Indies would set a dangerous precedent and could influence further slave revolts in the USA.
Jefferson - who was a slave owner himself - refused to recognize the negro government, rejecting diplomatic relations and even imposed an economic embargo on Saint Domingue in order to make the negro nation fail. Also, he had to face southern slave-holders reaction against the Saint Domingue in fear of similar outbreaks. Previous incidents like the Gabriel slave conspiracy in 1802 fueled this fear.
Some of the problems were gangs around the cities, low wages, and bad living spaces.
