Before World War I, German planners prepared for only one contingency: an all-out, two-front war. In July 1914, this made it difficult for Germany to match Russia's military preparations without automatically escalating into general war. Before World War II, French military planners also prepared for only one contingency: full-scale invasion of France. This made it difficult for France to react effectively when Hitler occupied the Rhineland in 1936. Both the German and French governments went wrong by assuming, rather than judging, where the main threat lay. Each country put tremendous effort into elaborating its war plans and force structure, down to the most minute detail. And yet each seems to have given only the most cursory attention to the political contingencies in which those plans and forces might have to be used. Hence the plans and force structures turned out to be not only irrelevant but-because of their rigidity-downright harmful.

These experiences, at which we will presently look in greater detail, offer lessons for those who formulate NATO policy. To avoid a similar distortion in NATO planning, we need to spend some time thinking about why the Alliance needs military strength before we engross ourselves in controversy as to how it should organize and use that strength. Such a review of likely contingencies suggests, for example, that the notion of stripping NATO down to a trip-wire, backed by massive strategic nuclear capabilities, makes very little sense. This proposal, so much discussed in the press, seems to assume that there is only one threat: that of deliberate attack. It wholly fails to take into account the threat of unintended conflict, and hence it fails to provide the forces needed to deal with this danger.


When most people think of Count Schlieffen, the talented soldier who was German Chief of Staff before World War I, they think of the war plan which he produced: the so-called Schlieffen Plan. From a military standpoint, this plan had considerable merit. It recognized that war, arising on either German front, would inevitably involve both Russia and France, in view of their alliance. It called, therefore, for Germany to invade France as soon as Russia began to mobilize for war. France would then be crushed before Russian mobilization could be completed. A two-front war would be avoided.

The trouble with this plan was that it was directed to the least likely threat: a deliberate decision by either the Dual Alliance or the Triple Entente to attack the other-out of the blue, so to speak. It was not well suited to the contingency which the events of 1908, 1912-13 and 1914 made clear was a more likely threat: that of a Balkan crisis, which both sides might wish to limit. In such a crisis, Germany would feel compelled to support Austria. If Russia mobilized, while negotiations were under way, Germany would wish to match her military preparations. But it was important that Germany be able to do this without automatically bringing on general war-so that diplomacy could have time to seek a peaceful settlement.

The war plan which Schlieffen had inherited from his predecessor, the elder von Moltke, would have permitted this. It called for Germany to stand on the defensive against France. Thus it did not require her to go to war in instant reaction to Russian mobilization. A perceptive view of the most likely threat would have led Schlieffen to be more cautious in discarding this plan. This is made evident by the events of July 1914.

A little before noon on July 28, Austria declared war on Serbia. Austria had long felt threatened by growing discontent among its Slav subjects, and considered this discontent compounded by the example and agitation of nearby Serbia. Since 1908 Vienna had been increasingly tempted by the idea of a war on Serbia, and on July 5, after Franz Ferdinand's assassination, it had secured a promise of German support. Austria then (July 23) delivered its ultimatum to Serbia. Belgrade's reply was conciliatory in tone, but it rejected the two key Austrian demands, thereby supplying the desired casus belli.

In offering Austria their support, German leaders had counted on being able to confine the war to Austria and Serbia. But Russian and other reactions to Austria's ultimatum had convinced the Kaiser, by July 28, that this judgment was probably wrong. That morning he suggested to his foreign minister that Germany begin to seek a negotiated settlement. Although he purported to base this suggestion on the mild tone of Serbia's reply, growing indication of allied hostility was probably a more important reason. As Virginia Cowles points out in her biography of the Kaiser: "He did not want a European war, only a European victory. And he suddenly saw that he was standing far closer to the edge of the precipice than he had imagined. In a flash all his martial ardour vanished. The dozens of marginal annotations he had made, with their peremptory demands and their fierce bravado, were instantly forgotten. From now onwards the Kaiser was interested only in maintaining peace. From now on, everything he did was born of a frantic effort to stop the cumbersome machine in time to avoid a crash. An overpowering fear had taken possession of his soul."

The German Chancellor and the German Foreign Minister took a dim view of the Kaiser's proposal. They still believed that an Austrian-Serbian conflict could be localized, and did not pass on the Kaiser's suggestion to Vienna till late the night of the 28th, and then only in greatly watered down form. But on July 29, as the news from allied capitals grew steadily worse, they also lost their nerve. They began to put more pressure on Vienna-without, however, threatening withdrawal of German support if it came to war. The Chancellor telegraphed to Vienna: "In these circumstances we must urgently and emphatically commend to the consideration of the Vienna Cabinet the acceptance of mediation on these honorable terms. The responsibility for the consequences that might otherwise arise would be for Austria and ourselves exceedingly grave." The Italian historian, Luigi Albertini, a sharp critic of German policy, comments: "The appeal was undoubtedly urgent and there is nothing to justify its being described as insincere."

Austria needed two weeks to complete her military preparations against Serbia. It is unlikely Germany could have persuaded her, in this period, to accept a peaceful settlement. Vienna was already far committed to war on the basis of previous German encouragement. But we will never be certain. For at 6 p.m. on July 30, after a number of more limited steps, Russia ordered general mobilization in order to put pressure on Austria to agree to a satisfactory settlement, and to prepare for the possibility of war.

Three hours later, unaware of this Russian decision, the German Chancellor, Bethmann-Hollweg, sent the famous telegram No. 200, reinforcing his previous urgings, to the German Embassy in Vienna. If Austria continued her present policy, he warned, "that would place us in an untenable position in the eyes of our own people. We can therefore only recommend most urgently that Austria should accept Grey's proposal. . . ." But at 11:20 p.m., after receiving a phone call from the General Staff, Bethmann-Hollweg instructed the German Embassy in Vienna to disregard telegram No. 200. An unsent telegram explained why: "I just suspended the execution of instruction No. 200, because General Staff just tells me that the military preparations of our neighbors, especially on the East, compel speedy decision. . . ."

We are still not sure what specific intelligence the General Staff conveyed to Bethmann. Probably there were some tentative indications of the recently ordered Russian general mobilization, plus hard news of previous more limited Russian steps. In any event, the basic point is that when major Russian military preparations became known in Berlin, German diplomatic efforts vis-à-vis Austria ended. For prompt German resort to war was then necessary, if the German military were to discharge their responsibility under the agreed war plan. A German ultimatum was sent to Russia the following day threatening her with war if she did not stop mobilization. When she refused, Germany declared war on Serbia, Russia and France, and directed her main armies against France, as per the Schlieffen Plan.

In theory, there was nothing to prevent Germany from changing that plan at the last minute, in order to avoid war and continue negotiations, despite the Russian mobilization. In practice, so many complex details were geared to the plan as to make the military pressures for holding to it very hard to resist. As the Chief of Staff said to the Kaiser when Wilhelm proposed another last-minute shift: "Such a change would bring to the frontier not an army ready to fight but a confused and disordered mass of armed men."

Thus, German military planning, by focusing only on the unlikely threat of premeditated war, made it difficult to deal with an Austro-Serbian crisis without rapid escalation into general war.


The same point-the need for realistic military planning-is underlined if we look at another case. After World War I, the French Government had to determine what military posture would best serve its political interests in Europe. When the question arose as to where the most likely threat to those interests lay, the French decided it, as Justice Brandeis would say, without answering it. They decided it by determining that the peacetime French army would consist only of cadres, which could not be operationally effective until their units were fleshed out by general mobilization. This, in turn, was a measure so vast in its impact on French national life that no government was likely to contemplate it, except in defense of France itself. Thus France could exert its power effectively only in response to a single contingency: direct invasion. As R. A. C. Parker pointed out in his discerning study of the Rhineland crisis in World Politics: "The French Army, indeed, had made plans since 1919 on the assumption that no action would be required of it in Europe short of a full-scale war."

In 1924, Paul Reynaud, then a rising politician, published an article entitled, "Do We Have the Army of Our Needs or Our Habits?" He argued that the real threat was not German invasion of France, but rather lesser violations by Germany of the Versailles Treaty, e.g. Germany's breaking the ceiling on its armaments or attacking its eastern neighbors. France needed, he suggested, a mobile standing army which could take the offensive quickly to right such violations. A conscript army could not meet this need, since the initial Treaty violations might be too ambiguous to justify such a massive measure as general mobilization.

His warnings met no echo until 1934, when a young and promising officer (then a protégé of Pétain), Lt. Col. Charles de Gaulle, published his book, "Vers I'Armée du Metier." This brilliant work translated Reynaud's general concept into a specific proposal-an all-professional armored force. In 1935 de Gaulle called on Reynaud, then a Deputy, and persuaded him to lay the proposal before the Chamber. When Reynaud did so in the debate of March 15, 1935, government spokesmen maintained that the existing military posture would meet the only real threat, invasion of France, and that there was no need to incur the expense of creating other forces as well. The Minister of Defense, General Maurin, concluded the debate: "The government, at least in my person, knows perfectly its plan of war."

The test of that plan was posed on Saturday, March 7, 1936. At dawn German troops occupied the Rhineland in defiance of the Treaties of Versailles and Locarno, proving Reynaud and de Gaulle right in their judgment of the threat. At 9:45 a.m. the French ministers met. Several demanded immediate action, but no decision was taken. At a second meeting in the early evening, it was decided to recall men on leave and order covering units up to the border.

On the following morning, Sunday, the Cabinet and the President of the Republic met in the decisive conference at 10 o'clock. The Prime Minister and the Foreign Minister both seemed to lean, in varying degrees, toward French military entry into the Rhineland. Then the Minister of Defense, the same General Maurin, lowered the boom. To move effectively, he demanded general mobilization. "To resort to general mobilization only six weeks before the election would be folly," one startled minister exclaimed. Another made the point more clearly: "We would be swept out of Parliament." Paul-Boncour, who was there, comments wisely that to ask for general mobilization to chase the few detachments Hitler had sent into the Rhineland was to terrorize the Council of Ministers and public opinion.

The political infeasibility of such a massive measure as general mobilization to deal with anything short of deliberate attack on France became evident. But Maurin insisted that to act he needed "the white posters, that is to say total mobilization." One minister, at least, was astonished at "the disproportion between the measure proposed and the operation in question."

The Prime Minister telephoned the Chief of Staff, General Gamelin. The General was confident that he could clean out the Rhineland, but to do this, he confirmed, he needed the means; and the means could be secured only through general mobilization. The reason, of course, was that an army of cadres could only move if those cadres were filled out by calling up reservists. Again, a prior decision on force structure proved irreversible in time of crisis. Faced with a choice between general mobilization and doing nothing, the Cabinet did nothing.

From then on, the story takes a melancholy turn. On March 10, the government read a declaration to the Chamber indicating that France would act only if her allies-notably Britain-went along. This was little but rationalization for inaction. As Churchill remarks in his memoirs, it was evident then that the only way to pull Britain along was for France to be willing to go ahead without her.

On March 11, Gamelin and Maurin responded formally to the government's earlier request for a study of possibilities for limited action. They suggested steps which were not only limited but irrelevant: either Franco- Belgian occupation of Luxembourg with that country's consent, or an advance to a maximum depth of six miles, on a front of only 24 miles, into the Saar- leaving the overwhelming part of the formerly demilitarized Rhineland under German military occupation. Even these steps would require mobilization of over a million men, and, if Germany resisted, general mobilization would have to follow immediately. On that same day Foreign Minister Pierre Flandin departed for London, where the lack of British interest put an end to what was becoming an increasingly academic discussion.

We now know that if the French had moved into the Rhine-land, Hitler would probably have withdrawn. He had apparently so decided beforehand, under pressure from his generals. And, in this event, the deterrence to further German aggression would have been very strong indeed.

The French could have moved if their prior planning had been based on a sound assessment of the contingencies that were most likely to arise, and if their force structure had been geared to these contingencies. Whether they would have moved is harder to say, for there was little public or parliamentary support. But some of the ministers saw the issue as it was. The most one can say is that there would have been a greater likelihood of action; if nothing else, the dependence on general mobilization gave the Cabinet a pretext for inaction.

Indeed, it is just barely possible that the mere existence of a mobile professional French army which was clearly designed to enforce the Treaty, and ready to move at a moment's notice, would have deterred Hitler from going into the Rhineland in the first place. As General Hering, who commanded at Strasbourg in 1936, wrote ten years later: "The situation would have been entirely different if we had, in peacetime, disposed of an assault force of a hundred thousand or so men, ready to march at the first signal." But, by defining the threat too simply, the French denied themselves this option.


NATO's political and military position is obviously very different from that of Germany in 1914 or France in 1936. But NATO could none the less make a mistake not unlike the one made by prewar German and French military planners, if its conventional forces became little more than a trip-wire to trigger nuclear retaliation. This change is sometimes suggested, in public and press discussion of NATO's future, as a means of reducing military budgets, while deterring deliberate Russian attack-either on a massive or a limited scale.

The risk of deliberate attack will remain so long as massive Soviet forces are at hand. But now, as before 1914, there is also the danger of unpremeditated conflict. Now, as then, that danger arises out of instability in Central Europe. Whereas in 1914, it was the disaffection of Slavs under German rule in Austria which helped to create that instability, today it is the disaffection of millions of Germans under Soviet rule in East Germany. As evolution proceeds elsewhere in Eastern Europe, the dangers to peace posed by Ulbricht's still rigid rule in East Germany may grow.

The problem is compounded by the existence of an isolated beacon of freedom in West Berlin, 100 miles deep in Communist territory. The several Berlin crises through which we have passed suggest that its vulnerable communication lines could be a tempting target (as Serbia was in 1914) for rulers hoping to meet insoluble domestic problems by striking at external influences that seemed to exacerbate these problems. If a Berlin crisis should some day lead to a local clash, this might trigger the very disorders the Soviets hope to avoid.

We need a NATO force structure which would permit us to deal with these possible forms of unintended conflict in ways that would fulfill the interests of all the allies, and with minimum risk of escalation. A trip- wire would, very clearly, not meet this need. A more substantial and flexible force structure is needed not only to cope with these contingencies, but to deter them. The Communists might not expect an instant massive Western nuclear response to the more ambiguous forms of pressure on Berlin's communications lines, for the same reasons that Hitler did not fear French general mobilization in 1936-the apparent disproportion between the threat and the proposed response. If, however, the Soviets see at hand a Western capacity for action on a more limited scale, they will take more seriously the possibility of an instant and effective Western response.

Now, as in 1936, however, the maintenance of an effective deterrent force will be prevented if the West proceeds from an unduly narrow assessment of the threat to an unduly narrow estimate of needed capabilities-if, in other words, it judges that the only threat is deliberate attack and that it does not need forces for deterring or dealing with other contingencies.

NATO now has substantial forces on the central front which can serve these purposes. We must resist the temptation, in the face of a diminishing threat of deliberate attack, to believe that such forces are not needed. We must not deprive ourselves of the "assault force, ready to march at the first signal," that General Hering found so sadly wanting in 1936.

Unintended conflict is not, of course, the only contingency that NATO needs to be able to handle. It requires a powerful nuclear and non-nuclear capability for dealing with deliberate aggression in various forms. It must be able to defend against such aggression promptly and with whatever weapons are needed to maintain the territorial integrity of countries under attack. What it needs, in short, is what Germany and France lacked before World Wars I and II: sufficient flexibility to respond to a wide variety of contingencies with means suited to each. NATO will be most likely to maintain this flexibility if, unlike prewar German and French planners, we assess realistically the kinds of threats that have to be faced before fixing our strategy and force structure.

You are reading a free article.

Subscribe to Foreign Affairs to get unlimited access.

  • Paywall-free reading of new articles and a century of archives
  • Unlock access to iOS/Android apps to save editions for offline reading
  • Six issues a year in print, online, and audio editions
Subscribe Now