The Danger of Historical Analogies: The South China Sea and the Maginot Line


Does China’s island building in the South China Sea resemble the Maginot Line? This is not a quirky and unimportant debate, but rather one that has profound strategic implications. A recent War on the Rocks article advances this argument. The authors, Robbie Gramer and Rachel Rizzo, write:

The Maginot Line became a ubiquitous symbol of failure in defense planning; an adversary that adapted its offensive strategy to bypass the line quickly rendered one of the strongest and most elaborate defense networks the world had yet seen irrelevant.

It then follows that if this comparison with China’s strategy in the South China Sea holds water, the People’s Liberation Army is engaged in an expensive, futile effort that leaves them destined to be out-flanked. But, what if this analogy is wrong, starting with their characterization of the Maginot Line? Like “Beam me up, Scotty,” or “Play it again, Sam,” (neither of which were actually said in Star Trek or Casablanca, respectively) popular references oftentimes diverge from reality. In this case, inaccurate recollections bring with it the potential for fatally flawed analogies.

The Origins of the Maginot Line

To begin with, it is important to recognize what the Maginot Line was and, as important, was not. The Maginot Line was initially intended as an economy of force measure, in the face of demographic realities (especially France’s gruesome losses in manpower during World War I), as well as the economic constraints of the 1920s and 1930s. French military policy, forced to adjust to the losses of millions of men, had to accept one year-conscription periods — hardly extensive training. At the same time, those same manpower losses, coupled with French industrial weaknesses, resulted in a faltering economy, further undermined by the effects of the global Great Depression. The creation of fortified belts would maximize the effectiveness of under-trained troops, allowing them to hold off substantially larger numbers of attackers while buying time for national mobilization.

In this regard, the Maginot Line served, first and foremost, to defend northern France, including the bloodily reclaimed Alsace and Lorraine, from German attack. The loss of the coal and steel production of northern France, as well as Alsace-Lorraine, had badly weakened the French war effort in the First World War. It was imperative to avoid a repeat of that catastrophe.

The Maginot Line, famously, did not cover the entire French border. Instead, it stopped at the junction of France, Belgium, and Luxembourg, in the Ardennes Forest area. This gap was intentional. It was the hope and expectation of the French high command to advance forward in the event of future hostilities with Germany and meet the enemy in Belgium — and more importantly, not in France. An advance into Belgium would support the Belgian army, and add several more divisions to the envisioned Franco-British forces. It would also stop the projected main German thrust, which was expected to be a recapitulation of the Schlieffen Plan of 1914. In fact, this was the German war plan — the original German “Case Yellow” invasion expected a thrust through Belgium and Holland that would drive the Allies back to the Somme, and then envelope the Allied line.

The Mechelen incident of January 1940, however, saw a copy of the German war plans accidentally fall into Belgian hands, and from there to the other allies. German operational security considerations demanded a reformulation. Subsequently, General von Manstein persuaded Adolf Hitler to back a plan developed by Gen. Heinz Guderian, shifting the main German thrust to the Ardennes. Thus, the outflanking of the Maginot Line was as much a function of luck as of deliberate planning. Ironically, the Allied powers might have fared much better had they not obtained Germany’s original war plans.

For the French, the greatest failing of the Maginot Line arguably lay not in its conception, but in the opportunity costs that its construction imposed. The 87 miles of fortifications that were completed by 1935 cost some 7 billion francs ($8 billion in 2015 terms), over twice the initial estimate when the effort began in 1930. Depending on the source, the entire French defense budget in 1935 was between 7.5 (John Mearsheimer) and 12.8 billion (Williamson Murray) francs. As a result of this stupendous outlay, French military development in all other areas, from tanks to aircraft, suffered.

The burden of the Maginot Line was exacerbated by failings in French industry, especially its aircraft sector, where neither engines nor aircraft design kept up with the latest developments. Similarly, while French tanks were numerous and well-armed, often with better weapons than their German counterparts, French armored forces suffered from a combination of poor doctrine (that called for the dispersal of armor among infantry rather than the concentration of armor that the Germans used to great effect) and problematic designs (single-man turrets, lack of radios). This meant that at the decisive point, German ground forces often had superiority of numbers, better doctrine governing their engagement, under solid air superiority.

Poor French strategy catastrophically brought this to a head. As noted, the Franco-British war plan was to advance into Belgium. But because Brussels had pursued a neutral stance for much of the 1930s, official staff talks between the Belgian military and their French and British counterparts had ground to a halt. Informal talks were limited to the highest levels, preventing effective coordination. Consequently, the planned advance was extremely vague. Full staff coordination was only revived in 1939, with the expectation that French forces would advance to the Dyle River in Belgium. But French Gen. Maurice Gamelin broadened French efforts further by preparing to advance French forces to Breda in Holland. While this would ostensibly add the Dutch army to the allied order of battle, in reality it would deprive the French of any meaningful strategic reserve, as their lines extended ever further. When the Germans broke through the Ardennes, there were no available forces to stem the tide.

In short, France in 1940 labored under a host of disadvantages, including a weak economy, limited manpower resources, poor industrial organization, inadequate doctrine, and a bad strategy, hampered by poor allied coordination, and amplified by happenstance. The Maginot Line didn’t help, but it was hardly the sole factor in the “strange defeat” of June 1940 (indeed, it was among the last parts of the French military to surrender).

Why China Is Not the Third French Republic

To what extent, then, does contemporary China suffer from problems comparable to those of 1940, and does their island and reef expansion exacerbate them in the way the Maginot Line did with France over 70 years ago? At present, and for the foreseeable future, China will not be as economically weak or as demographically crippled as France was in 1940. For all the demographic problems that confront China due to the combination of the one-child policy, an aging society, and male-female imbalance, China has not suffered the relatively abrupt destruction of so many of its young men, as France did during the Great War, which in turn affected everything from economic output to conscription period. China’s demographic problems will emerge more gradually (although it would appear that China’s workforce has already begun to shrink, as the average age steadily rises), potentially reducing the need for drastic, disruptive measures.

Similarly, despite a slowing economy and a volatile stock market, China’s economy and industry do not seem to be suffering from the same structural, systemic weaknesses that plagued the French economy and industry in the 1920s and 1930s. For all the problems in China’s state-owned enterprise system, for example, there does not appear to be the same problem of an “artisanal, small-firm nature of the aircraft industry” as marked the French aircraft industry prior to World War II. Similarly, China does not seem to exhibit the same weaknesses in research and development, or the ability to produce new weapons designs as plagued the L’Armee de l’Air. Fifth-generation designs are transitioning from the drawing board to China’s airbases. Indeed, the development of the anti-ship ballistic missile, a capability unparalleled by other states, would suggest an ability to foster some level of indigenous innovation.

The substantial Chinese economic capacity also fundamentally invalidates the analogy of China’s efforts in the South China Sea to the Maginot Line. Jonathan Kirshner of Cornell University explains, “From the end of 1927 through the middle of 1936, France spent 6 billion francs on fortifications and 3.4 billion on weapons.” (Like figures on the French defense budget of the time, figures on how much the Maginot Line cost also vary by source.) The official Chinese defense budget for 2015 is about $145 billion, which is almost certainly less than actual defense spending. It is difficult to imagine that the construction in the South China Sea represents so large a proportion of the Chinese defense budget that it crowds out weapons acquisition or research and development. The steady overall modernization of the People’s Liberation Army would seem to indicate otherwise.

All this places the Chinese efforts to physically prepare the battlefield, consistent with their doctrinal imperatives, in a very different light from that of France in the interwar period. It should be clear that, whereas “from the outset fortifications were a confirmation of the [French] army’s weakened state, a sign of the altered military balance between France and Germany,” the same is not true for China, especially relative to the United States.

Why the South China Sea Islands Are Not a Maginot Line

The Maginot Line, by absorbing so much of the French defense budget, was probably a bad idea, even if it was not nearly as responsible for the defeat in 1940 as is often presumed. Are the artificial islands the Chinese are building in the South China Sea a bad idea, and therefore comparable to the Maginot Line?

Certainly, it is possible that the islands are sufficiently expensive that they are imposing an opportunity cost on the Chinese national security budget, even if it is not as extreme as the cost of the Maginot Line relative to its budget at the time. Given the opaque nature of China’s budget process, and the lack of good data on what actual Chinese defense spending is, it is difficult, if not impossible, to assess this burden. If the islands can be circumvented or bypassed, as Gramer and Rizzo suggest, then they are indeed a waste of money. But it is by no means clear that this will be true.

In the first place, it is not clear that the islands are intended to be the main shield for China’s defense. In the end, these are small islands in the large South China Sea; far from being a continuous belt of defenses (as with the Maginot Line), they are far more likely to be the equivalent of a picket line, providing an outer sensor and defense line for “continental China” (i.e., the Chinese mainland including Hainan Island). As such, their purpose is to provide early warning of an impending attack, compelling an adversary to deploy their forces in advance of reaching their main targets. This would seem consistent with indications that fighter strips, radars, and surface-to-air missile batteries are being constructed on these islands. Not only would radars and combat air patrols likely detect any aerial assault, but the need to neutralize the forces on those islands would take time, while depriving any forces aimed at the mainland of surprise. Such capabilities would also make vaulting over them a risky proposition.

A picket line can be avoided by air forces, at the cost of greater fuel expenditure and potential loss of surprise, but in the case of maritime movement, any attempt would potentially canalize American or other nations’ forces into different lines of approach. Those lines of approach, in turn, could then be more heavily defended, whether by mines, Chinese diesel-electric submarines, or fast attack craft (whose range could be extended if based from these new islands). Forces deployed on these islands may therefore intercept U.S. forces on their approach to the mainland.

The potential ability to ambush or attrit American naval forces becomes especially important in terms of killing American attack submarines. Given the American advantage in undersea warfare, the Chinese are likely to devote significant resources toward countering American submarines, including detecting and prosecuting them as far away from China as possible. The airstrips being constructed could easily support anti-submarine warfare helicopters and maritime patrol aircraft. The islands could also serve as data fusion centers for China’s developing body of underwater sonar arrays, such as those China is already testing in the region. In this regard, the islands might be comparable, not to the Maginot Line, but the Greenland–Iceland–United Kingdom (GIUK) gap, through which Soviet submarines had to transit if they wanted to reach the North Atlantic sea-lanes. The GIUK was not envisioned as an impenetrable barrier, but as a filter, imposing costs upon an adversary each time they transited through it. The Chinese may well see these artificial islands as serving a similar purpose.

A picket line can be reduced, but that would take time, and would also absorb resources. Attacks against the islands would mean platforms and munitions diverted from targets on the mainland. Losses inflicted on those platforms would weaken follow-on attacks. Meanwhile, vulnerabilities identified in, for example, the drone swarms suggested by Gramer and Rizzo (e.g., operating frequencies) would be exploited in subsequent engagements. All of this would make ensuing operations that much more costly — and therefore raise doubts in the adversary’s mind about the likelihood of success.

It is this last aspect where the Chinese islands might parallel the Maginot Line. French decision-makers hoped that they might deter Germany from going to war at all. The Maginot Line, ideally, would disrupt German timetables, giving France a chance to mobilize sufficient forces that, in combination with British, Belgian, and other forces, might cause Berlin to pass on war. Thus, the Maginot Line would serve as a military means to a political end.

The Chinese are likely to harbor the same hope: If their forces on the artificial islands in the South China Sea can inflict enough damage, consume enough time, deny enough advantages (e.g., surprise), then an adversary might choose not to challenge Chinese actions. Those actions, however, unlike Germany’s, would not be aggressive or territorially aggrandizing (at least in Chinese eyes). Instead, Beijing would be securing claims to what it has consistently claimed as its own territory, whether it is the South China Sea or Taiwan. Through military preparation of the battlefield, China would hope to achieve its political goals.


Dean Cheng is the Senior Research Fellow for Chinese political and security affairs at the Heritage Foundation. Prior to joining the Heritage Foundation, he worked at the Center for Naval Analysis, and SAIC. He enjoys long walks on short piers.


Photo credit: Mass Communication Specialist 2nd Class Joe Bishop, U.S. Navy