Under the Treaty of Alliance (1778), the United States agreed to protect French colonies in the Caribbean in return for their support in the American Revolutionary War. As the treaty had no termination date, this obligation technically included defending them from British and Dutch attacks during the 1792 to 1797 War of the First Coalition. Despite popular enthusiasm for the French Revolution, there was little support for this in Congress; neutrality allowed Northern shipowners to earn huge profits evading the British blockade, and Southern plantation-owners feared the example set by France's abolition of slavery in 1794.