Iran’s sixteen-hundred-mile-long border with the Soviet Union was a vital element in Western security considerations after World War II for several reasons. First, the quickest way for the Soviets to reach the Persian Gulf was to head directly south from the Azerbaijan Socialist Republic and through western Iran. Second, the Soviets had occupied Iranian territory south of that border more than once and after World War II attempted to do so again. Third, the contiguity of Soviet territory with northern Iran allowed the Communists to establish covert support bases in efforts to undermine local Iranian authority. Later, American policymakers and intelligence officers found this border vital to U.S. national security programs.8
Of almost equal import were the long borders Iran and the Soviet Union each shared with Afghanistan: an invading Soviet army transiting the Afghan frontier and thence into eastern Iran would be unhindered in its pathway to the Arabian Sea, the Strait of Hormuz, and Iranian and Arabian oil reserves.9 In short, a Soviet invasion of Iran, whether from north to south (through Azerbaijan) or from east to west (via Afghanistan), would find it easy going. Such an invasion would give the Soviets control over the vital Strait of Hormuz, through which passed 40 to 60 percent of the world’s oil supplies. Further, U.S. policymakers postulated that if Iran were permitted to fall into the Soviet sphere of influence, American prestige in the region would be severely diminished, perhaps undermining the will of other Middle East countries to resist Soviet expansionism.10 Finally, in the days before long-range jet transport aircraft, Soviet control of Iran and the immediate region would have created a grave logistics challenge in moving troops and supplies from Europe to the Far East in the event of conflict in that arena.11
After the 1953 coup, when the United States became inextricably entwined in Iran’s future, additional factors increased Iran’s importance to America and the West in general.12 Iran under the shah commenced an extensive modernization program while adopting a staunchly pro-West, anticommunist political posture. Because of the unusually personal nature of the relationship between the shah and the U.S. government, the two countries not surprisingly came to share similar views of the region’s security requirements.13 As time passed, Iran took on increasing importance as the guarantor of security for the Persian Gulf and Strait of Hormuz.14 By the 1960s the oil that transited the strait was bolstering the economies of America, Europe, and Japan. If one believes that a strong economy is essential for national security and defense, then Iranian oil was doing much more than simply providing cheap gas and profits for petroleum companies.
One other aspect of Iran’s geographic location made it vital not only to the interests of America and the West in general, but to the security of the whole world. Beginning in the late 1950s, the U.S. intelligence community placed signals intelligence listening posts in Iran along the Soviet border. There were ultimately seven sites in the Elbourz Mountains of northern Iran, the most important being the two code-named Tacksman.15 Tacksman I, located at the southeastern corner of the Caspian Sea near the village of Behshar, was established in the late 1950s. Tacksman II, constructed in 1964–65, was located well into the mountains 40 miles east of Meshad, outside the village of Kabkan. From Kabkan electronic eyes enjoyed unobstructed “line-of-sight” views across the vast open spaces of the Kara Kum Desert and the flatness of the Uzbek plain into the Kazakh SSR (see map 1). There, barely 650 miles north-northeast of Kabkan, near the city of Leninsk (Tyuratam) on the banks of the Sar-Darya, sprawled the Baikonur missile testing complex. (The town of Baikonur was actually a bit more than 300 miles from Tyuratam; the Soviets gave the name Baikonur to the missile complex to disguise its location and confuse Western intelligence.16 Thanks to U-2 and satellite imagery, this ploy didn’t work.)
In the 1950s and 1960s the Soviets tested their liquid-fueled intercontinental ballistic missiles (ICBMs) at Tyuratam, and Tacksman II could monitor every missile launched from that site toward the Kamchatka Peninsula to the northeast. Sophisticated Tacksman II equipment could acquire the telemetry signals almost at liftoff and then continuously record the telemetry through the missile’s midcourse trajectory, before the second stage of the rocket fired. This early signal acquisition allowed more precise evaluation of the data with respect to throw-weights, range, reliability, missile dimensions, and so on.17 It also allowed Tacksman II to inform other signals acquisition sites around the world to activate their equipment in preparation for the missile’s arrival within their windows.18
The intelligence listening posts could also eavesdrop on Soviet ground and air communications and were vital for monitoring the development of the Soviet Strategic Missile Forces beginning in the early 1960s.19 More important, they were invaluable in the 1970s for verifying the Strategic Arms Limitations Treaties (SALT) with the Soviet Union and efforts to reduce the prospect of global nuclear war.20
The importance of the Tacksman sites to U.S. policy was clearly delineated in an October 1974 memorandum from the Department of State inspector general to the secretary in response to a National Security Council directive. The secretary was advised that U.S. policy toward Iran should be to “ensure the maintenance and unimpeded use” of the intelligence facilities in Iran, the memo giving clear recognition of the need to sustain a stable government in that country. With that objective in mind, the inspector general “urged” the department to “undertake a long-range study of U.S.-Iran relations and ensure a high level of monitoring” of this relationship.21 The Tacksman sites thus constituted a crucial element in the U.S.-Iran equation.
Map 1. Former Soviet Socialist republics to the northeast of Iran
It took World War II to create what appeared to be a permanent alliance between Iran and the United States.22 Although the 1939 Nazi-Soviet Nonaggression Pact apparently raised no concerns in the American legation in Tehran when it became public knowledge, the April 1941 Nazi invasion of Greece did. Two factors were at play: there was an established German commercial and political presence in Iran reaching back several decades under Reza Shah, and the Nazi-Soviet pact left open the possibility of Soviet demands to operate from Iranian airfields, a situation the impotent Iranian army would be powerless to prevent. The geopolitical matrix was further complicated when neighboring Iraq expelled the British in favor of ties with Germany.23 Because of the war in Europe, British Royal Navy and Royal Air Force units in the Middle East and Persian Gulf were thus forced to rely on Iran even more than previously for fueling stations and replenishment facilities. Then, on 21 June 1941, three German army groups invaded the USSR, one of which (Army Group South under Field Marshal Gerd von Rundstedt) headed for the Trans-Caucasus region in southwestern Russia, toward the Caspian and Iran. The British and the Soviets—suddenly allies—immediately insisted that Iran expel all German nationals, of whom there were some three thousand, among them intelligence agents who had been establishing underground networks in the country.24 The Iranian monarch, Reza Shah, refused.
With vital trans-European lines of transport and communication to the USSR severed, there remained only two avenues of supply by which vital U.S. Lend-Lease and other materials could reach the Soviets: the treacherous Murmansk run for ship convoys, and the Trans-Iranian Railroad from the Persian Gulf to the Soviet border in northwestern Iran.25 The solution was the occupation of Iran in the north by Soviet troops and by British forces in the Gulf region to facilitate the movement of Lend-Lease goods.26 Reza Shah, whose army was