Hazards of Sea-Land Alliances
Image Credit: U.S. Navy

Hazards of Sea-Land Alliances


Our senior students took the Strategy and Policy final examination late last week and acquitted themselves well, as usual. One quixotic thing about the U.S. Naval War College is that few students or faculty – even mariners who go down to the sea in ships – take much interest in the history of the sea, let alone in sea-power theory. For a variety of reasons, students look at the writings of Alfred Thayer Mahan, the U.S. Navy’s intellectual father, much like Superman looked at kryptonite. Questions about martial enterprises like counterinsurgent warfare are far more popular, probably because that’s what the respondents have done for most of their careers. Such material has immediate use, especially for practical-minded U.S. Army and Marine students. It concentrates minds, and understandably so.

The maritime questions we offer on our exams attract few takers. True to form, one question was very lonely this term. It asked what strategic difficulties beset sea powers that ally themselves with land powers in wartime, and how these difficulties might be overcome. While we look to history to get some purchase on vexing matters, this question commands more than antiquarian interest. Distinguished pundits increasingly enjoin the United States to retire to a more “offshore” posture, shedding overseas entanglements while sparing itself the burdens and hazards such entanglements entail. As a corollary, Washington should loosen or terminate longstanding alliance commitments. Forced to it, an offshore United States would exert power by forming temporary coalitions with land powers in embattled theaters. The Eurasian rimlands would remain the most likely candidates for U.S. military action. Washington should get involved as late in the day as possible, letting prospective allies bear most of the costs of fighting a would-be “hegemon,” or tyrannical power.

Having shamefully failed to convert a single student to the true religion of sea power, let me venture a few thoughts of my own about one of the chief pitfalls of land-sea coalitions – that continental states regard maritime states as undependable allies. Now, Mahan imbues sea power with romanticism. In the Napoleonic Wars, he writes in one of his best turns of a phrase, the “far distant, storm-beaten ships” of the Royal Navy, “upon which [Napoleon’s] Grand Army never looked, stood between it and the dominion of the world.” By shielding the British Isles from a cross-channel invasion, interdicting French shipping, and protecting British merchantmen who conveyed raw materials and finished goods hither and yon, the Royal Navy kept Great Britain in the fight and prosperous enough to fund a series of coalitions with the likes of Prussia, Russia, and Austria. Eventually, one coalition held together long enough to overcome Napoleon, until then a master alliance-breaker. Sea power was the enabler for victory on land.

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And Mahan’s right about this. There’s no gainsaying the worth of maritime command. Ruling the waves opens up a host of possibilities for shaping events on shore, where great disputes are ultimately decided. But seafarers perform their duties out of sight of land. Their efforts feel abstract to soldiers on the ground who fight and bleed. Continental rulers tire of seagoing allies’ appearing to free-ride on the labors of armies. And there’s something to this perception. In the 18th century, for instance, Prussia’s King Frederick the Great accepted British subsidies to finance wars against Russia and Austria. But, over time, Frederick wearied of acting as the “continental sword” of British sea power. In the wars against Republican and Napoleonic France, writes University of Reading professor Colin Gray, “London was prepared to subsidize continental allies; make a modest gesture of support on land, command at sea, and secure enemy colonies and overseas trading networks; and arrive at the peace conference as the organizer and paymaster of victory, economically probably strengthened by the conflict.”

In short, Britain wanted to help others in the course of helping itself – and reap rewards that would long outlast the war. It’s unsurprising that a continental power would take a jaundiced view of an ally that joined the cause reluctantly and belatedly, and having telegraphed its goal of escaping the commitment at the earliest possible moment. If the United States withdraws from commitments of decades’ standing and makes it known that it will return only to decide the outcome of a system-shattering war, its leadership will find it hard to rally durable coalitions. Contributing as little as possible to the cause, moreover, flouts an iron law of alliance management – namely that the power that contributes the most manpower and resources earns the dominant say in important decisions.

Appearing flighty and self-serving, then, is no way to lead a coalition. Great Britain ultimately bowed to this logic. It ended up sending major expeditionary forces to help overthrow Napoleon, the Kaiser, and Hitler. In short, sea powers have to go ashore, and be prepared to stay there, and convince continental powers of their stalwartness, if they want to be considered trustworthy.

Sure, the United States can revert to exploiting what founding father George Washington called its “detached and distant situation,” which “invites and enables us to pursue a different course.” It can heed John Quincy Adams’s injunction against going abroad in search of monsters to slay. This is counsel from wise men. Still, there are opportunity costs to pursuing a separate destiny from Asian and European nations after decades of exercising world leadership. Leaving may be easy; going back will be hard. U.S. leaders and the electorate must not make a decision of such moment without careful forethought.

James Holmes is an associate professor of strategy at the US Naval War College. The views voiced here are his alone.

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