MORE than once in this Bicentennial year I have found myself asking the question, What would have happened if Cornwallis had been defeated at Yorktown? There was a time when no respectable historian would allow himself to be caught playing with such fanciful hypotheses, but now that Clio has equipped herself—at least for occasional wear—with the blue jeans of the social sciences it is only necessary to call our iffy questions "counterfactuals" for them to pass muster in her wardrobe. And indeed it is perhaps profitable to consider for a moment what consequences would have flowed from a British defeat in 1781.

I do not have to stress what a close shave it was. Everything, after all, hinged on command of the sea, that fickle element which has brought so many well-planned strategies to ruins. True, from 1778 onwards the British had been able to thwart every attempt by the French to hamper the sea communications of the British forces, but one did not have to be superstitious to believe that this only increased the chances of their luck turning against them next time, If the two British naval squadrons, Hood's coming up from the West Indies and Graves's coming from New York, had not been able to intercept Barras bringing his siege artillery down from Rhode Island, Barras, in conjunction with De Grasse's substantial fleet, would have been able to land men and artillery at the Chesapeake with fatal consequences for Cornwallis's poorly defensible entrenchments. The way would have been clear for Washington, reinforced to a strength of 16,000 troops, to overwhelm Cornwallis's 6000, Cut off from reinforcements by