Potsdam Conference: Sitting (from left) Clement Attlee, Ernest Bevin, Vyacheslav Molotov, Joseph Stalin, William Daniel Leahy, James F. Byrnes, and Harry S. Truman.

THE United Nations have as yet made no authoritative statement of their attitude toward the future aviation activity of the former Axis countries. Yet decisions in this field cannot be long delayed.

On December 26, 1945, following the Moscow Conference, the Foreign Ministers of Russia, Great Britain and the United States announced the procedure for the preparation of the peace treaties with Italy, Rumania, Bulgaria, Hungary and Finland. Such treaties, after being drafted by certain of the Great Powers, are to be submitted to an international peace conference scheduled to be held in May. At some later date, and under some procedure not yet announced, the peace terms to be imposed upon Germany and Japan must be fixed. The treaties with the minor enemy powers and the eventual terms to be imposed on Germany and Japan must each contain definitive air clauses. A clear understanding of the method and degree of control of military and civil aviation which is to be imposed upon the major and minor enemy countries is essential.

Little of our past thinking on this subject is of value today. The distinction between "civil" and "military" aircraft, and the theory that the former cannot be converted to use as bombers or fighters, no longer can provide us with a sense of security. The potentials of aircraft and airborne missiles are changing too rapidly to permit the old distinction to carry much meaning. We are now aware that an atomic bomb can be launched from a "civil" aircraft. The destructive power of the atomic bomb is still unmeasured and our ability to control its development and use is the most pressing problem of civilization.

The process of contraction in time and space, and the accompanying intensification of our danger in the event of war, continue unabated. While this paper was in course of preparation, for example, press dispatches on almost successive days announced: 1, the non-stop flight of a jet-propelled plane, burning cheap commercial kerosene, from Long Beach, California, to New York -- a distance of 2,470 miles -- in four hours and 13 minutes, at an average speed of 584 miles an hour; 2, the successful use of a commercial-type cargo plane in test jumps by parachute troops; 3, a statement by the retiring Chief of United States Army Ordnance that the Army possesses radio-controlled rockets capable of rising 50 miles above the earth, with the implication that research may produce rockets which can be dispatched to any point in the world.

The same power unit used for the jet-propelled bomber and fighter will also drive the transport in the near future. The controlled rocket is their first cousin. Instruments, parts, techniques for military and civil aircraft are quite interchangeable. Civil transport planes built to carry 80 passengers overnight across the Atlantic will quickly strip down to carry, perhaps, double that number of armed men. A hundred such transports might deliver an equipped military division across a continent or an ocean. If the same 100 transports each carried a few atomic bombs, a war might begin and end in a few hours. These are hard facts. There must be no mistake in the new peace treaties. If air disarmament of an enemy nation is required, then we must ask whether that nation must not be deprived of its entire right to fly.

Air power is the ability of a nation to act through the airspace, in other words, to use controlled flight -- such, for instance, as the flight of aircraft. It is part of national power, to be used at home or abroad, in peace or in war. Though its uses are various, both military and civil, it is basically indivisible. The armed air forces represent but one use of the nation's air power. Civil and commercial aviation are supported by and spring from the same basic national elements. If these continue to exist or are uncontrolled, it is utterly futile to expect success from compulsory prohibition of any particular use of air power. Evasion is too practicable.


The Treaty of Versailles was supposed to disarm Germany in the air permanently. An army of limited size, and a restricted navy without submarines, were to be permitted, but German military air power was to disappear completely: Germany was not even to possess a token air force with which to threaten Europe. And the victors in the First World War were no less resolved that this disarmament would be immediate. As Foch is reported to have said at one of the conferences preparatory to the final adoption of the air clauses of the Treaty: "No delay should occur in depriving the Germans of their military aircraft which had wrought such evil work throughout the war in connection with the unjustifiable bombing of open towns. The conference should, therefore, adopt the principle of the aerial disarmament of Germany."

Disarmament, then, was supported by all the Allied and Associated Powers; but the means by which it was to be accomplished brought months of disagreement. The intent to disarm Germany was plain; the result of the steps taken to give this intent effect was complete and tragic failure. The method used -- an attempted separation of the military and civil uses of air power -- was artificial and unrealistic. It failed. The German air force reappeared, and Munich and World War II soon followed. The method would fail again.

The discussion at Versailles centered on the problem whether civil aviation must be prohibited in Germany and other states in order to attain effective military air disarmament. As Brigadier-General Groves (of the British Army) pointed out 11 years later in his memorandum to the League of Nations on "The Relations between Civil and Military Aviation," the Supreme Council at Versailles overruled the views of the aeronautical experts as to the practical difficulties of dealing separately with civil and military aviation, and "accordingly the Peace Treaties provided that the late enemy powers should be forbidden to possess any military (including naval) aviation, but should be allowed to develop civil aviation." What General Groves modestly did not say was that he, personally, had taken part in the discussions at Versailles and had warned that "It would, therefore, be very difficult to prevent Germany setting up a large potential military air service under the guise of commercial enterprise."[i]

The original records are quite clear. All of the technical experts on the Aeronautical Commission, except the American representative, insisted upon a long period of prohibition against the manufacture of any type of aircraft in Germany -- civil as well as military. The direct question propounded to each technical representative was whether, after the Treaty of Peace and in view of the easy transformation of commercial aircraft into weapons of war, it would "be necessary to prohibit civilian aviation in Germany and all other enemy states." Each member of the Aeronautical Commission, except the American, answered "yes," disagreeing only as to the length of the period of prohibition. The French representative insisted that this period should last at least 20 or 30 years, due to the impossibility of foreseeing progress in flying in the immediate future.[ii]

When the question came before the Supreme Council, President Wilson personally intervened and insisted upon separate treatment of military and civil aviation. Mr. Ray Stannard Baker, in explaining the American attitude as presented at Versailles by President Wilson and Mr. Lansing, has pointed out that the Americans desired Germany to be completely disarmed in a military sense but that "what they wanted to avoid was a long-continued, irritating interference with the economic life of the enemy nations -- which they believed would lead speedily to future wars."

The American position having been finally accepted in the Supreme Council and in the Council of Foreign Ministers, the so-called Air Clauses of the Treaty to provide for military air disarmament were included in Part V, the Military, Naval and Air Clauses. The Aerial Navigation Clauses dealing with German civil aviation were separately drafted by the Aeronautical Commission and included in the Treaty as Part XI. The Aeronautical Commission also drafted at the same time the International Air Navigation Convention. The two sets of clauses in the Peace Treaty and certain clauses in this Air Navigation Convention must be considered together if the situation in Germany after World War I is to be understood.

The Air Clauses of the Treaty are Sections 198 to 202, inclusive. They were never abrogated and were theoretically still in force until the outbreak of World War II (except for Hitler's unilateral repudiation of the entire Treaty). They were expected to result in the permanent disarmament of Germany.

Article 198 categorically and without time limit provided that: "The Armed Forces of Germany must not include any military or naval air forces." The remaining articles required demobilization of the personnel of the German air forces within two months; authorized the aircraft (presumably military) of the Allied and Associated Powers to fly across and land in Germany until the final evacuation of their troops; forbade for six months after the coming into force of the Treaty the manufacture in Germany or importation of aircraft, aircraft engines and parts; and required delivery within three months by Germany to the Allied and Associated Powers of all military and naval aeronautical material, including aircraft, hangars, engines and instruments. The last mentioned clause, covering delivery of aircraft and aeronautical material, was significantly qualified with the proviso that the materials to be delivered will include "all items . . . which are or have been in use or designed for military or naval aeronautical purposes." The article was amended to include this limitation at President Wilson's specific suggestion, as part of his insistence on minimum interference with German economics. He repeatedly stated that it was impossible to suppress everything that might be used in war.

Clauses 203-210 of the Treaty authorized the creation of Allied Control Commissions to enforce the Military, Naval and Air Clauses.

The Aerial Navigation Clauses of the Treaty are found in Part XI, Articles 313-320. In view of the decision of the Supreme Council not to prohibit German civil aviation, as such, these clauses were drafted to cover the right of civil aircraft of the Allied and Associated Powers to fly into and over Germany and to participate in her traffic. They jointly constitute a license for that purpose and thereby tacitly recognize continued German sovereignty over German airspace. This license no more affected such sovereignty than does any other aerial navigation license given by one sovereign state to the civil aircraft of another sovereign state.

Taken together, the Aerial Navigation Clauses, effective for a limited period ending not later than January 1, 1923, gave to the civil aircraft of the Allied and Associated Powers rights of transit over and landing in German territory (including the use of airports open for national public traffic), subject to German flight regulations and airport charges, providing that such regulations and charges were applied equally to German aircraft; required recognition by Germany of certificates of aircraft nationality and airworthiness, and of airmen's licenses issued by the Allied and Associated Powers; and required Germany to enforce over her territory as to her aircraft, the rules as to lights, signals and air traffic to be set up under the separate Air Navigation Convention, which would be binding upon their own civil air organizations. This Convention was being drafted at the time. When adopted by the Allied and Associated Powers, it was to control international aviation as between themselves and such countries as might later adhere.

The Aerial Navigation Clauses, when first submitted by the Aeronautical Commission to higher authorities of the Allied and Associated Powers, were so drafted as to continue in effect, apparently, until Germany was either admitted into the League of Nations or authorized, by consent of the Allied and Associated Powers, to adhere to the Air Navigation Convention. Mr. Lansing promptly and vigorously objected for various reasons, but particularly because no reciprocal rights were given to future German civil aviation in the territory of the Allied and Associated Powers. The latter objection is again of great interest as indicating the desire of the American delegation to interfere as little as possible with German civil aviation: the American assumption was that German aviation would play a useful part in the reconstruction of German economy. The discussion ended in a compromise. A section was included in Clause 320, providing in substance that the civil air rights in Germany of the Allied and Associated Powers should lapse on January 1, 1923, unless before that date Germany was admitted to the League of Nations or became a party to the Aerial Navigation Convention.

It should be noted here that while Article 200, part of the Air Clauses, gave "the aircraft of the Allied and Associated Powers" freedom of transit over Germany and the right to land in German territory, this clause was apparently always construed by the parties as applying solely to military aircraft. Otherwise it would have been inconsistent with the limited license privileges in the Aerial Navigation Clauses.

The Air Navigation Convention was drafted by the Aeronautical Commission. Its main purpose was to provide principles and rules for future international air commerce, including uniform regulatory practices. It recognized the fact that each state had sovereignty over its airspace, but provided, as between contracting states, for reciprocal freedom of passage of aircraft except that "the establishment of international airways shall be subject to the consent of the states flown over."

When first drafted, it contained no provision for the ultimate adhesion of enemy states. Lansing again objected, on the ground that this limited the development of German civil aviation too harshly, and the Aeronautical Commission was directed to include such a provision. As finally adopted, the Convention authorized adherence of the states which took part in the war but which were not signatory to the Air Navigation Convention (i.e. the enemy states) only if they became members of the League of Nations, or -- in the period up to January 1, 1923 -- if adhesion were approved by the Allied and Associated Powers. After January 1, 1923, adhesion was possible if agreed to by three-fourths of the signatory and other adhering states. The importance of this provision appears from the text of the much-discussed Article V. As adopted, it provided that "no contracting state shall, except by a special and temporary authorization, permit the flight over its territory of an aircraft which does not possess the nationality of a contracting state."

The language of this clause represented one of the few victories of the experts who thought it necessary to limit German civil flight in order to obtain military security. Its intention was clear. Any state which adhered to the Convention could not admit German aircraft to its territory. States which did not adhere to the Convention could not fly into territory of the Allied and Associated Powers. It was hoped, as one of the negotiators frankly admitted,[iii] that the Convention would have the effect of placing Germany inside a ring-fence: that is to say, she would not be able to fly outside of her own frontiers.

The situation at the conclusion of the Versailles Conference can, therefore, be summed up as follows: (1) Germany was to be disarmed by the surrender of military and naval aeronautical material; by the demobilization of her armed air forces; by the prohibition for six months of the manufacture of aircraft, engines and parts; and by the permanent prohibition of the inclusion in her armed forces of any military or naval air force. (2) The aircraft of the Allied and Associated Powers were permitted for a period not beyond January 1, 1923, to have civil aviation rights into and over Germany, and to participate in her air traffic; Germany was not to have reciprocal rights in their territory. (3) Germany could organize and develop her civil aviation within Germany, and internationally to and with such other states as might be able to and would agree. (4) Future international air traffic between the Allied and Associated Powers was to be developed under the Air Navigation Convention. Neutral states could participate in this traffic only by adhering to the Convention, in which case they were not to allow the flight into their territories of German aircraft, unless and until Germany was allowed to adhere to the Convention.

The Allied objectives were the permanent military air disarmament of Germany, and possible limitation of German civil aviation within German territory. Except as indicated above, Germany was left in sovereign control of her own airspace, with adequate power to reorganize her civil aviation, and without any control as to the training of pilots and other personnel.

The basis of German air power -- its right to fly -- still existed.


The Allied objectives were never attained. By 1929 German civil aviation was the most important in Europe. By 1934 her armed air force not only was in existence but was far in front of the air forces of other nations.

How this happened is a long story. A summary is sufficient to show the futility of the whole Versailles approach to the control of air power.

The Allied Air Control Commission and the German authorities quickly disagreed as to which aircraft and equipment were military and which were civil. Pending clarification, the Allies prohibited the manufacture of aircraft and engines beyond the original six-months' Treaty period. German aircraft manufacture was resumed in 1922. In the autumn of 1920, the Supreme Council had instructed the Aeronautical Commission to draw up rules to distinguish civil from military aviation. The Commission insisted that this was impossible, but was again directed by the Supreme Council to prepare the rules. After months of discussion the so-called "Nine Rules" were adopted over vigorous German protest, and were put into effect only after the delivery of an actual ultimatum. The Rules were harsh and artificial. Included in "military" aircraft (the manufacture and use of which were prohibited) were all aircraft which could exceed a speed of about 106 miles an hour at a height of about 6,500 feet, or carried fuel for more than four hours' flight at full power, or could transport total cargo in excess of about 1,320 pounds, including pilot, crew, passengers and freight. After continuous quarreling between the Control Commission and German authorities, these Rules were modified in 1925 so that a "civil" aircraft could carry a load consisting, approximately, of a pilot, seven or eight passengers, and a few hundred pounds of baggage and express -- in other words, a total of approximately 2,000 pounds. In the meantime Allied civil aircraft exceeding these specifications were being used all over Europe in civil operations, giving Germany a sound argument as to the utter artificiality of the Nine Rules. Here was a clear instance of the impracticability of the attempt to differentiate between military and civil aviation. In the meantime, to avoid these prohibitions, German manufacturers had set up branch plants in adjoining countries and were making admittedly military planes, as well as civil aircraft.

The limiting clause of the Air Navigation Convention was also causing trouble. Due to Germany's geographical position, such neighboring neutral nations as Holland, Denmark and Switzerland found it more important to develop international air traffic with Germany than with the former Allies. This was lawfully possible so long as they did not adhere to the Convention as drafted. Article V of the Air Navigation Convention was not building a civil air ring around Germany; on the contrary, special provisions had to be made to modify this article so as to permit contracting states to conclude special conventions for interchange of air traffic with non-contracting states. German air power was still in existence and another loophole was opening for its expansion.

On January 1, 1923, the Aerial Navigation Clauses of the Versailles Treaty ceased to be effective and Allied flying rights into Germany ended. Due to the feeling created by the occupation of the Ruhr, Germany withdrew from pending negotiations for her adherence to the Air Navigation Convention. Germany now had full sovereignty of her own airspace, unencumbered by an Allied license to fly. Promptly taking advantage of this tactical position, Germany forbade the entry into her territory of Allied aircraft, and began to confiscate those that did land. In the meantime her own civil aviation continued to grow. According to figures submitted to the League of Nations in 1930, German aircraft by 1925 were flying more kilometers than were the commercial planes of any other European nation, and her lead continued to grow for the next several years. The effort to control German civil aviation had broken down so completely that it soon became advantageous for the former Allies to try to persuade Germany to adhere to the Air Navigation Convention. Even this was never accomplished.

The strength of Germany's civil aviation forced a revision and the virtual abandonment of attempts to control her military air development. Under the new agreements of May 1926 between Great Britain, France, Italy, Belgium and Japan on one side and Germany on the other, military aviation theoretically remained forbidden in Germany, but the Allied military air control authorities ceased to exist. Military air training was theoretically prohibited, but German civil aviation was to be "kept within the limits of normal development . . . in regard to commercial aviation, which shall not be subsidized in excess of these requirements." Provision for inspection or control ostensibly passed to the League of Nations. There is no evidence that the League ever acted. It is questionable whether it had any inspection or other organization to warn of German military air rearmament, or enforce the supposedly still existing restrictive covenants of the Versailles Treaty against such rearmament. Germany was apparently left to police herself. Military air rearmament under the Nazis had been made easy. On the conclusion of the May 1926 agreements ending military control, direct arrangements to exchange civil air traffic were made between Germany and several of the former Allied countries.

The attempted division of military and civil aviation had failed. Germany's right to fly, and her "know-how" gained through manufacture of aircraft and training of personnel, ostensibly for civil and commercial purposes, had led to the logical result predicted by the air experts at Versailles.


The dilemma which faced President Wilson and the other Chiefs of State of the Allied and Associated Powers at Versailles in 1919 must be faced again, but under infinitely more difficult and complex circumstances. The grave possibilities of the use of air power in the new atomic era pose questions which will make world history.

A basic decision about policy is necessary. If we feel that the past behavior of the enemy Powers requires that in the present world situation we disarm them in the air, it is useless for us to consider again an artificial separation of military and civil air power. Enemy air power must be attacked and controlled at its base. Several analyses of air power have been published. None seems to meet the present situation. Air power has one basic element which eclipses all the others -- the right of a nation to fly and to exercise sovereignty over its airspace.

Air power, as stated earlier in this paper, is the ability of a nation to act through the airspace, to use controlled flight, at home and abroad, in peace and in war. No matter what the nation's resources may be and what other elements contribute to its air power, it must control the airspace over its territory and have the right to use that airspace for such purposes as it may determine. Otherwise its air power is practically non-existent.

If the future military disarmament of an enemy state is necessary for security purposes, the right of the state to use its airspace must be prohibited or fully controlled. Nothing else will prove satisfactory. This is the lesson of the Versailles failure.

Under international law, each nation normally has sovereignty over its airspace. In the language of the new "Convention on International Civil Aviation" adopted at Chicago in 1944 and now awaiting ratification: "The contracting States recognize that every State has complete and exclusive sovereignty over the airspace above its territory." Language to the same legal effect is in the Air Navigation Convention mentioned earlier and adopted simultaneously with the Treaty of Versailles; in the Pan American Convention on Commercial Aviation, adopted at Havana in 1928 (to which the United States is a party); and in the separate statutory provisions of practically every nation. Under this theory of sovereignty, a nation uses its airspace as it may determine and can exclude all others therefrom except as and when general or specific permission may be granted. This is the basis of national air power.

In like manner the government of the homeland may use its sovereignty over its colonial possessions to the exclusion of others and to advance or defend its national aims. Peace terms necessary for future security may well require enemy states to relinquish sovereignty over colonial or other territorial possessions. Such sovereignty will doubtless be vested, temporarily or permanently, in a trusteeship set up under the United Nations Charter.

Exactly the same thing must be done with the airspace over those enemy states which are to be disarmed. Even if some are not to be permanently disarmed, temporary trusteeship of the airspace would offer the simplest and soundest method of readjusting world aviation. While the United Nations Charter may not have specifically foreseen this procedure, it can be construed to meet the situation. Certain surface controls should also be vested in the United Nations agency. These include provisions for the international control of airports in enemy territory and for the prohibition of the manufacture of aircraft, engines, parts, the training of personnel and the storage of raw material and fuel.

Under such a system, policing would be comparatively simple. No aircraft could use the airspace of the present enemy states until licensed by the United Nations agency. No military air force could be built up under the guise of a commercial organization. The control would also be flexible. Such air transportation as was needed for the rebuilding of the economy of an enemy state could be provided as the United Nations agency might determine. When any enemy state is considered to have so reorganized its government as to warrant its admission into the United Nations Organization, the airspace trusteeship could be relinquished.

In the meantime the problem of Axis air power must be considered as a whole. Treaties being drafted for the minor enemy states, discussions of economic terms for Germany proceeding at Berlin, control directives prepared for Japan in Tokyo -- all must face the same problem and face it consistently. Can any of the enemy states at this time be vested with control of the airspace until the rest of the world knows much more than it does now of the future use of air power? The United Nations Organization has been set up to prevent aggression and preserve the peace. It should be trusted and given adequate power and authority to that end in the air as well as at sea and on the ground.

[i]Cf. "Papers Relating to the Foreign Relations of the United States: The Paris Peace Conference, 1919," v. IV, p. 337. Washington: Department of State, 1943.

[ii]Cf. Ray Stannard Baker, "Woodrow Wilson and World Settlement." New York: Doubleday, 1923, v. I, p. 414.

[iii] Baker, op. cit. v. II, p. 458.

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  • JOHN C. COOPER, of the Institute for Advanced Study, Princeton University; formerly Vice-President, Pan American Airways
  • More By John C. Cooper