The common method of comparing the strength of one navy to another is to count the number and size of usable warships, and this is undoubtedly a valid way to begin because sooner or later an inferiority of warship strength had serious consequences. Yet tonnage alone did not signify naval power. This point is illustrated in the second half of the century, when the combined warship tonnage of the navies of France and Spain gradually rose to a figure well above that of the British navy, yet Europeans then feared British naval power more fervently than they had feared it during the first half of the century, when British tonnage exceeded that of any combination of rivals by a wide margin. This came about, it will be seen, in consequence of a fundamental shift in British naval strategy.

The argument that underpins this chapter may be put crudely as follows. Building warships, even very good warships, was rather easy. Consistently repairing and replacing them over the years was harder. Manning them with competent seamen, feeding those men and preserving their health was harder still. And, finally, keeping squadrons operating at sea, especially for extended cruises and on distant deployments, was hardest (and most expensive) of all. The peculiarity of British naval power during the eighteenth century was that it was so steadily employed at sea, actively doing the work of seapower.