Most people call it the American Revolution, some call it the American Secession, but Gordon Tullock calls it the War of the American Revolution:
In fact it was a world war with major naval battles in the Indian Ocean, and almost the whole of Europe involved. Militarily the American theater was a sideshow. Further, what little fighting there was in that theater normally resulted in American defeats. Washington was a very good strategist, but a poor tactician and our troops rarely stood up to a British bayonet charge.
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It occurred to France that since a third of the English lived on the west shore of the Atlantic, it might be possible to stir them up so that they became independent, thus greatly weakening England. Agitators, money and arms were employed to this end. Whether the American colonies would have revolted even without this support is unknown. Certainly their success would have been dubious.
In any event the uprising was apparently popular. The elected colonial legislatures everywhere supported it and, apparently local governments did so also.
Further, the British were unable to place small garrisons in the countryside, which made it impossible for them to get the area under their control. Their experiment in New Jersey led to the small garrisons in Princeton and Trenton being beaten by Washington’s army. This was, incidentally, his only real victory before Yorktown. His strategic ability, which led him to realize the importance of an army in being which made it impossible for the British to divide their army up into small local garrisons was vital.
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In Yorktown [Cornwallis] was in a familiar position for a British general, in possession of a port and awaiting the Royal Navy to reinforce or evacuate him. Washington, here demonstrated his fine strategic sense He arranged for De Grasse to come up from the Indies, thus interrupting his campaign to reclaim the sugar isles, and with Rochambeau he marched south, managing to get away from New York without fighting. The march was uneventful except that the American troops refused to go on until they had been paid. The French provided the money.
The joint army at Yorktown was almost 4 times as large as Cornwallis’s force. Further, although Cornwallis might have been willing to take on an American force larger than his, half of them were French. Meanwhile, the other part of Washington’s plan brought DeGrasse’s fleet to blockade Yorktown. A British fleet under Graves met DeGrasse off the Virginia capes, but after a brief cannonade, withdrew, Cornwallis was doomed. This tiny naval action should be listed as one of the decisive battles of history, but normally is not.
After Cornwallis’ surrender the war continued, mainly without much fighting in the American Colonies, but with active naval campaigns.
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The independence of the American colonies, which was the principal French objective, was achieved. It seems likely that had the French revolution not broken out, they would have been partitioned by the European powers. Certainly the Continental Congress was worried enough to make Hamilton a lieutenant General to organize their defenses.
Washington was successful in New Jersey because local Jerseyites waged a guerrilla war. The British believed the moderate middle colonies would be easier to pacify than radical New England, especially New Jersey which was full of apparently amiable Dutch settlers.
They didn’t take into account their Protestant Reformed faith. The Dutchmen had a schism in the 1740s Great Awakening. The ones that stayed loyal to the church governing body in Amsterdam also supported the British. The more evangelical members that wanted ecclesiastical freedom fought for independence.
The patriot militias eventually fought better than the colonial army. By 1879, the British had lost control of New Jersey, and it basically turned into a civil war between each side of the schism.
In every major 18th-Century conflict between France and the Brits, the French navy got outspent by the Royal Navy and got beaten. The one war they didn’t get beaten badly on the seas was the American war, which was also the only war in which they were able to outspend the Royal Navy. They were able to do that because they didn’t need to deploy a large army on the continent, and the brits did need to spend money deploying one in America. The land campaign in the US was not a sideshow; it was a very large drain on British resources that made the success of the other campaigns possible.