Had we been fighting for independence from any country other than England, the French would not have helped.
True, we needed the "edge" from the french to get us over, but we could have done it with out them. The war would have taken longer, but we would have won anyway.
Now, don't let your current passions cloud history. Fact is, if de Grasse had not bottled up the English, the Americans would have had to deal with the English fleet (under Adm. Thomas Graves), and the English soldiers would have had an escape, and a chance to live and fight another day.
Fact is, we could NOT have done it without the French.
Rochambeau had a hell of a lot more men on the ground than Washington. The French Fleet under de Grasse intercepted the British Fleet and whipped them on the way to relieve Yorktown.
A typical revolutionary soldier in the later years of the war carried a French Musket, Shot, and Powder. Wore a uniform made in France, including boots and a newfangled invention called socks, ate French rations, carried his French overcoat and blanket in a French knapsack, and was backed up by French artillery. If he got wounded, he was treated with a French medical kit (no thanks!) and French medicines.
The trouble we were giving Britain was definitely worth the money to our Froggie Friends. Von Steuben was definitely a help too, in that he made us ready to accept professional help from the French. But that doesn't mean we should sell the French connection short. We woulda lost big time without their help, regardless of their motives.