Domestic politics, moreover, can upset the soundest strategic schemes. Alliances are fissile things, dependent on the vagaries of domestic politics among their members. It remains unclear whether the fleet-unit approach is popular enough in Britain to endure changes of party. Indeed, it’s unclear whether officialdom has even explained the approach to ruling elites and rank-and-file Britons in strategic terms. If not, an Anglo-American division of labor has little political ballast to it. If a cost-cutting exercise—not conscious strategic choice—brought London to its new fleet design, then future rounds of budgetary debate could see the concept discarded on similar penny-pinching grounds.

That’s what happens when saving money takes precedence over strategic effectiveness. If operating two Queen Elizabeth ships and their stealth aircraft proves pricier than forecast—hardly an unlikely prospect—the carriers themselves might come under scrutiny. Having reduced the Royal Navy to a couple of fleet units to save money, lawmakers might deploy the same bean-counting logic to justify dismantling the fleet units themselves. Allied effectiveness would suffer.

That domestic politics intercedes in strategy and fleet design hardly constitutes a novel observation. Adm. J. C. Wylie points out that lawmakers make strategic decisions through what they choose to fund—and not to fund—all the time. Heck, dominion governments didn’t submit meekly to Great Britain’s modular fleet design a century ago. Mindful of Canada’s modest GDP and bicoastal geography, for instance, Canadian leaders protested the expense of a cruiser/destroyer force. And they objected to British plans to base the Royal Canadian Navy fleet unit in the Pacific. A westward orientation, they complained, would leave Canadian interests in the Atlantic unguarded except through the good graces of Britain’s navy. What made sense for imperial defense made a tough sell with Canadian constituents.

Carl von Clausewitz would nod sardonically at all of this. The martial scribe observes that everything in strategy is simple, yet “the simplest thing is difficult.” Minor difficulties “accumulate and end by producing a kind of friction” that impairs rational strategy-making and operations. And Clausewitz is alluding to friction within a single state’s military and diplomatic apparatus. Trying to orchestrate multinational strategies, forces, and doctrine only compounds friction in the machinery’s innards.

In particular, half-heartedness bedevils allied ventures. “One country may support another’s cause,” contends Clausewitz, “but will never take it so seriously as it takes its own. A moderately-sized force will be sent to its help; but if things go wrong the operation is pretty well written off, and one tries to withdraw at the smallest possible cost.” Tepid political commitment begets lackluster strategic results. Clearly, then, a modular transatlantic fleet design will not come together or sustain itself of its own accord—any more than it did within the British Empire in days of yore.

Executing such a design will take constant, painstaking effort. Like all alliances, coalitions, and ententes, an Anglo-American navy—if indeed one is in the offing—will demand careful tending from diplomats and senior commanders on both sides of the Atlantic. Let’s not entrust alliance-building and maintenance to shipwrights and tacticians.

James Holmes is a professor of strategy at the Naval War College and coauthor of Red Star over the Pacific (second edition forthcoming 2018). The views voiced here are his alone.

Image: Britain's Queen Elizabeth waves to British Royal Navy crew members performing a salute on the HMS Bulwark amphibious assault ship during a tour of the Grand Harbour in a traditional Maltese fishing boat at the State Visit and Commonwealth Heads of Government Meeting (CHOGM) in Valletta, Malta, November 28, 2015. REUTERS/Toby Melville​