Iran has always been a major factor in the politics of the Gulf region. This of course was, and is, due to many factors that include its strategic position, its large population and its mineral wealth, i.e. oil (despite the fact that this factor was added as a result of the annexation of the Arab emirate, Arabistan, to the Persian state following WWI).
In fact, in talking about Iran’s regional ambitions, one must not ignore the fact that during the last four centuries, and following the collapse of the different Arab empires in the region, Iran (the Safawid empire) and Turkey (the Ottoman empire) remained the only dominant powers. This historic domination gave rise to certain residual historical claims that are demonstrated every now and then in the two countries’ politics. But while the modern Turkish state did not as a rule pursue these claims, modern Iran has.
There are several examples of this. The occupation of the three Arab Gulf Islands, the two Tumbs and Abu Musa, following the withdrawal of the British forces from the region in 1970 is an obvious one. Other less apparent examples are the Iranian attempts to influence or interfere in other Gulf countries, including Bahrain and Iraq. Iran, under the Shah, tried to be the only major power in the area, the ‘policeman’ of the Gulf and a state with the fourth-largest army in the world. Thus Iranian military advisors and agents and sometimes military units were often present in different parts of the Gulf, and wherever the Shah felt an expedient opportunity to infiltrate. By far the most obvious example was the Shah’s heavy involvement in Iraqi Kurdistan between 1961 and 1975, which succeeded in securing all Iran’s objectives in the Shatt al-Arab waterway and the Arabian Gulf without any real opposition.
It is interesting to note that these ambitions did not change following the overthrow of the Shah’s regime in 1979. The new Islamic regime in Iran remained loyal to all these strategies and ambitions. In fact, one can confidently say that the new Islamic Iranian regime went a step further in this direction by giving itself the right to topple any regime it did not like by introducing the concept of "exporting the revolution," a doctrine that entailed the use of force if necessary. The war against Iraq was the best example.
Although the old Iraqi regime of Saddam Hussein was held responsible for expanding and enlarging the conflict, Iran instigated the conflict with the intention of spreading its influence and example of government into Iraq. The ayatollahs thought Iraq, a country with a Shiite majority, would welcome such a change, which in turn would lead to other changes in the Gulf area and total Iranian domination of the region. Of course, this ambition was not achieved for many reasons, but cardinal among them was Iraqi opposition.
Following the 1991 war, which resulted in the elimination of Iraq as a regional power, Iran emerged once again as the sole power in the Gulf. It was, however, psychologically and morally contained, a containment instigated by the US and some other regional powers such as Turkey, Saudi Arabia and Israel, to prevent Iran from taking advantage of the defeat of the Iraqi army following the liberation of Kuwait.
A new phase in Iran’s regional role has now arisen after the occupation of Iraq. The destruction and occupation of the only regional power directly able to contain Iran holds mixed opportunities for the country. On the one hand, the occupation ended the Iraqi state and created a power vacuum there that Iran is more than eager to fill. On the other hand, it brought Iran’s archenemy, the US, to its border. The US, almost immediately, and one should say foolishly, started to issue threats against Iran even before completing the occupation of Iraq. Iran, feeling threatened, decided to take advantage of the chaotic situation in Iraq and facilitated the infiltration into Iraq of elements hostile to the US, while at the same time assisting its own allies in the Iraqi state.
Iran’s current strategy appears to be two-pronged. With one eye on its own ambitions, and another wary eye on the US, Iran is hoping to either turn the events in Iraq to its benefit or, at the very least, keep the American forces bogged down in Iraq, thus not giving the US the time and opportunity to invade Iran based on the Iraqi example.