Islands in the stream
Information Dissemination, the weblog of someone who describes himself as an "armchair admiral", looks at the the disposition US fleet units in Persian Gulf. Whether or not you believe there are going to be offensive operations against Iran, Information Dissemination has an interesting discussion of what naval objectives are important.
In particular any naval conflict with Iran, whether of a defense or offensive nature will require the capture of several Iranian held islands in the middle of the waterway in the Gulf of Hormuz. The islands, Siri, Abu Musa and the Tunb group "are arsenals on the deep water channel in and out of the Gulf, they will require Marines to secure in a war against Iran". The Tunbs, incidentally, are claimed by the UAE. Wikipedia writes:
In 1971, shortly before the end of the British protectorate and the formation of the UAE, Iran seized semi-control of Abu Musa under an agreement of joint administration together with Sharjah, with both sides nominally upholding their separate claims. A day later, on 30 November 1971, Iran forcibly seized control of the Tunb Islands, against the resistance of the tiny Arab police force stationed there. The Iranians were instructed not to open fire, and the first(and according to some sources only) shots came from the Arab resistance which killed 4 Iranian marines and injured one. According to some sources, the Arab civilian population of Greater Tunb was then deported, but according to others the island had already been uninhabited for some time earlier.
In the following decades, the issue remained a source of friction between the Arab states and Iran. The Gulf Co-operation Council of Arab litoral states repeatedly declared support for the UAE claims. Bilateral talks between the UAE and Iran in 1992 failed. The UAE have attempted to bring the dispute before the International Court of Justice, but Iran refuses to do so. Tehran says the islands always belonged to it as it had never renounced possession of the islands, and that they are an integral part of Iranian territory. The UAE argue that the islands were under the control of Qasimi sheikhs throughout the 19th century, whose rights were then inherited by the UAE after 1971. Iran counters by stating that the local Qasimi rulers during a crucial part of the 19th century where actually based on the Iranian, not the Arab, coast, and had thus become Persian subjects.
The maritime importance of Iran's island positions can easily be seen from this Wikipedia map, showing the island's position in relation to the sealanes.
Logically any naval confrontation with Iran would imply an amphibious operation to taking out these islands and the "armchair admiral" advises his readers to watch for the deployment of such forces when assessing the likelihood of conflict with Iran. Readers should bear in mind, however, that given the limited distances in the Gulf, a shore to shore operation might be conceivable.
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