Why did powers such as the French, Spanish and Dutch begin to support the Colonists during the war?

France's help was a major and decisive contribution towards the United States' eventual victory and independence in the war. However, as a cost of participation in the war, France accumulated over 1 billion livres in debt, which significantly strained the nation's finances. The French government's failure to control spending led to unrest that eventually culminated its own revolution a few years after the conflict between Britain and the United States concluded.