A piece from Asia Times poses some questions about the choke point at the end of the Arabian Gulf here:
The conventional wisdom is that either country would do so by mining the strait, something that happened in the war between Iraq and Iran in the 1980s. The conventional American military wisdom has always been that if a country attempted to mine the strait it might cause some short-term disruption, but that US naval assets would clear it in relatively short order.The Caitlin Talmadge article, "Closing Time: Assessing the Iranian Threat to the Strait of Hormuz" can be downloaded in pdf format here
But a new analysis suggests that the reality is actually more complicated and less sanguine than conventional wisdom suggests. It finds, "The notion that Iran could truly blockade the strait is wrong - but so too is the notion that US operations in response to any Iranian action in the area would be short and simple."
The key question is whether Iran can harass shipping enough to prompt US intervention in defense of the sea lanes. According to Caitlin Talmadge, a political science doctoral candidate at the Massachusetts Institute of Technology, who writes in the current issue of International Security journal, the answer, especially since the United States has long pledged to keep the strait clear, is yes.
Talmadge notes that Iran possesses a larger stockpile of missiles and mines 10 times as powerful as those used in the tanker wars of the 1980s, the last period of sustained naval conflict in the gulf. Even if Iran managed to lay even a relatively small number of these mines the US certainly would act to clear the area. But, she writes, "The experience of past mine-warfare campaigns suggests that it could take many weeks, even months, to restore the full flow of commerce, and more time still for the oil markets to be convinced that stability had returned."
Projections based on past instances of US mine-clearing operations indicate that it could take a month or more to reopen the Strait of Hormuz if Iran were allowed to initiate even a small mine-laying campaign.
Even worse, if the US decided to clear the strait of mines, the potential for further military escalation would be high. In part, this is because United States' mine warfare assets are designed to be used only in non-threatening environments.
Thus, the US would want to locate and destroy any sources of Iranian attack on its mine countermeasure (MCM) ships. Specifically, it would want to eliminate Iran's land-based, anti-ship cruise missile batteries. The aerial hunt for these assets could add days, weeks, or even months to the time needed to clear the strait, and quickly develop into a large and sustained air and naval campaign.