Royal Navy power had two different strategic effects separated by roughly forty years. During the Franco-Prussian War, Britain's commercial presence discouraged France from interfering freely with German trade. By World War I, alliance with Britain allowed France to transfer much of the wider maritime burden to the world's leading naval power. Diplomacy and coalition structure can therefore alter the fleet a state must provide for itself.
Notable Point · 32:18-33:55
Alliance with Britain changes France's naval burden
British sea power first constrained French action against German trade, then allowed France to hand major naval responsibilities to an ally in World War I.