Iran had long distrusted the British and the Russians. However, it had confidence in the United States and looked to the Americans as a force that would help maintain the country’s independence.
The conviction seemed validated when President Roosevelt pressured the USSR, Britain, and Iran to sign a Tripartite Treaty of Alliance consisting of nine articles and three annexes, all conforming with the principles of the Atlantic Charter and supporting America’s long-range goals in the Middle East.
The agreement, signed in Tehran on January 24, 1942, acknowledged the presence of foreign troops. but declared that signatories would respect the territorial integrity, sovereignty, and political independence of Iran. It also assured that Allied forces would withdraw from Iranian territory not later than six months after an armistice or peace.
Not surprisingly, Iran’s prior experience with Britain and Russia led the Iranian government to express its skepticism regarding the guarantees of the treaty. Bruce Kuniholm says:
As early as October 1941, uncooperative Soviet behavior was reported to the Department of State. Besides demonstrating a general unwillingness to cooperate, the Soviets sealed off their area of occupation and pursued a course that included administrative disruption, sympathy for separatists, political intrigue, and propaganda. In October 1942, the Soviets made grain purchases which worked to the detriment of the local population. While the State Department assumed such purchases were based on dire need, later Soviet actions indicated that their intent was to use the grain as a political tool. British Contravention of the Atlantic Charter’s principles in Iran is less obvious. While it seems unquestionable that the British were involved in political intrigue, much of what they did, so far as American sources reveal, appears to have been a product of the American ambassador’s unfounded suspicions rather than fact. The reason for this seems to be that in Iran, unlike Greece, the principles of the Atlantic Charter suited British (and of course American) purposes.
The principles of the Atlantic Charter called for, among other things, the access of all states, on equal terms, to the trade and raw materials of the world. It also respected the right of all peoples to choose the form of government under which they would live, with sovereign rights and self-government restored to all those who had been forcibly deprived of them. Stalin observed that the Atlantic Charter seemed to be directed against the Soviet Union and accepted it only on condition that its principles not deny the frontiers occupied by the Soviets when Germany attacked in 1941.
The Iranians continued to pressure the US to counterbalance British and Soviet interference in their affairs.
American missions essentially took control of the Iranian army and gendarmerie.
Along with the wartime arrival of an eventual 30,000 American troops, cooperation between the two countries increased, culminating in a US Army Mission (ARMISH). The purpose of this mission was “to enhance the efficiency of the Iranian Army through cooperation with the Ministry of War and the Iranian Army command.”
At the same time (as will later become clear), the close relationship with Iran conveniently allowed the US to expand its interest in the country’s oil.
By the conclusion of World War II, conditions were in place that ensured America’s continued influence in Iran.