Foreign Relations of the United States, 1950, The Near East, South Asia, and Africa, Volume V

782.5/8–1450

Memorandum by the Assistant Secretary of State for Near Eastern, South Asian, and African Affairs (McGhee)¹ to the Deputy Under Secretary of State (Matthews)

top secret

[Washington,] August 14, 1950.

Subject: The capability of Turkey to deal effectively with an attack by Bulgaria in which the Soviets do not overtly participate.

Discussion:

1. An attack on Turkey by Bulgaria, with or without overt Soviet participation, would be launched through Thrace—an area of some 9,000 square miles which constitutes Turkey-in-Europe. Historically, Turkey has shown its vulnerability in this area and on several occasions, such as in 1877 and 1912, the fall of Istanbul, which lies at the extreme eastern tip of Thrace, has been averted only through the political intervention of various of the Great Powers.

2. The vulnerability of Thrace is even greater now than in the pre-World War I era as there are very few obstacles to cross-country movement in dry weather and advance could be rapid with motorized equipment. There are believed to be no major permanent fortifications in the area of the Bulgarian-Turkish frontier, the only permanent installations of defense in European Turkey being the Catalca defense lines (less than 30 miles west of Istanbul) which protect Istanbul and the Bosphorus from land attack from the west, and the fortifications in the Gallipoli peninsula which commands the western entrance to the Straits.

3. Turkey at present has three Armies, made up of an estimated 16 infantry divisions, 3 cavalry divisions and 6 armored brigades, with a total strength in the neighborhood of 235,000 men. The Turkish First Army, with headquarters in Istanbul, has primary responsibility for the defense of Thrace and the Istanbul area. It is believed to have stationed in Thrace 4 infantry divisions, including 2 in the Gallipoli area, and 1 armored brigade. In addition, there are a number of supporting units—field artillery, tank destroyers and antiaircraft units—attached to the Army and Corps headquarters, although no accurate assessment of their effectiveness can be given. Two infantry divisions, 1 cavalry division and 1 armored brigade of the First Army are believed to be stationed in the area between Izmit and Istanbul in Asiatic Turkey. The Second Army, with units stationed in the western half of Asiatic Turkey, is generally considered as a reserve pool and could probably provide reserve units for the First Army. It is unlikely, however, that units of the Third Army, stationed in eastern Turkey, would be withdrawn from that area to assist in the defense of western Turkey.

4. Bulgarian forces are estimated to be the best trained and best equipped among the Soviet satellite forces. Reports indicate that Bulgaria has completed plans for mobilization in the event of an emergency, and it is estimated to have more than 600,000 men who have received “complete” military training. Estimates of the current strength of the Bulgarian Army have varied between 85,000 and 150,000, including 1 tank division and 2 independent tank brigades which are believed to have available 350 Soviet T–34 tanks and 50 obsolescent German mark IV’s. These forces are generally distributed throughout the country, but are in a position to be moved rapidly into any of the border areas. The troops near the Turkish border are in the normal summer maneuver area, and according to available reports, have not been alarmingly augmented, although there has been a strengthening of the border guard in this area. The Soviets have for some months been stockpiling war materials in the Balkans, particularly Bulgaria, in excess of the normal needs of the indigenous forces.

5. The Turks would be faced with the likelihood of the loss of all of Thrace in the event of a major Bulgarian attack with overt Soviet participation and would probably use their defenses in Thrace primarily for delaying tactics in an endeavor to withdraw their main forces to the Asiatic side of the Straits. However, in the event of a purely Bulgarian attack, the Turks might be successful in holding part of Thrace, at least at the Çatalca Lines and at the Gallipoli peninsula:

a) The Turks would undoubtedly mount a determined defense at the Çatalca Lines unless the Bulgarian advance were so rapid and powerful that the Çatalca Lines were breached before additional Turkish forces and equipment could be moved into the area and unless the Turks were deterred by fear of attack on other parts of the country or the fear of imminent overt participation by the Soviets in the Bulgarian offensive.

b) A Bulgarian attack, without overt Soviet participation, would probably have limited air cover, and little Turkish air support would probably be given Turkish ground forces in Thrace. However, some air support might be supplied by the British who with the French would be expected to come to Turkey’s assistance by virtue of their 1939 Alliance with the Turks,² which was reaffirmed in 1949.³

6. In the event that the Bulgarians should succeed in occupying all of Thrace, with the exception of the Gallipoli peninsula, any further advance—into Asiatic Turkey—would be unlikely. In that area comprising 287,000 square miles of Turkey’s total land area of 596,000 square miles, Turkish forces should be able to cope with any purely Bulgarian attack. The Turks have stationed there an estimated 12 infantry divisions, of which at least 5 have been supplied with and are being trained in the use of modern equipment, and 5 armored brigades which are being modernized and reequipped under the United States Military Aid Program. The terrain would be more defensible and the mobilization of reserves, in this area where most of the reserves are located, would substantially increase the size of the defending forces. The important ports of Izmir, Mersin and Iskenderun could undoubtedly be kept open to receive supplies and equipment.

7. A Bulgarian attack on Turkey, without overt Soviet participation either through direct support or through a simultaneous attack on Turkey in the east or elsewhere, is not considered likely unless it is one phase of an over-all Soviet plan of conquest which the Soviets recognize will start a world conflict:

a) In view of present relations between Bulgaria and its neighbors, Yugoslavia and Greece, Bulgaria would undoubtedly have to devote some of its forces to protect these flanks, thereby limiting the size of the forces and the amount of equipment it could throw against Turkey, which in turn would have direct bearing on its ability to overrun Thrace.

b) A Bulgarian attack on Turkey could be expected to bring Great Britain and France into the conflict as allies of Turkey, with the possibility that the United States would likewise become involved. Allied assistance would lessen the probabilities of the success of such an attack. Even if not furnished in time to prevent the Bulgarians from overrunning Thrace, it would make their hold on the area much more tenuous and their prospects for further advances on Turkish territory even more limited.

c) Control of Thrace and the capture of Istanbul would not in themselves appear to offer conspicuous advantages to Bulgaria or the USSR outweighing the risks of inviting a major war. Bulgaria would not control the Straits if, as expected, the Turks could hold the Gallipoli peninsula, nor would they accomplish the destruction of the Turkish Army or the occupation of Asiatic Turkey.

Conclusions:

1. A Bulgarian attack on Turkey, without overt Soviet participation, might accomplish the occupation of Thrace, with the exception of the Gallipoli peninsula, but a further advance into Asiatic Turkey would be unlikely.

2. The occupation of Thrace would not appear to bring advantages to the Bulgarians or Soviets that would compensate for the risk of inviting a major war. Hence, a Bulgarian attack on Turkey, without overt Soviet participation, does not appear likely unless it is undertaken as one phase of a Soviet plan of conquest which the Soviets recognize will probably start a world conflict.

1. Burton Y. Berry, Acting Deputy Assistant Secretary of State for Near Eastern, South Asian, and African Affairs, initialed this paper for Mr. McGhee. C. Robert Moore, Officer in Chargé, Turkish Affairs, drafted it.
2. Signed at Ankara, October 19, 1939; League of Nations Treaty Series, vol. cc, p. 167; also Britisli Cmd. 6165, Treaty Series No. 4 (1940).
3. See footnote 1, Foreign Relations, 1949, vol. vi, p. 1682.