Tehran is acting out, but it doesn't actually have much power to imperil U.S. interests in the region
Iranian Supreme Leader Ayatollah Ali Khamenei wipes his eyes while giving a speech in Tehran / Reuters
Iran this week punctuated ten days of naval exercises in the Strait of Hormuz and threats to close it with a warning to U.S. Navy ships to stay out of Persian Gulf, which requires passage through the strait. The tough talk may have temporarily juiced oil prices, but it failed to impress militarily. Recent news reports have cited U.S. military officials, defense analysts and even an anonymous Iranian official arguing that Iran likely lacks the will and ability to block shipping in the strait. That argument isn't new: Iran's economy depends on shipments through the strait, and the U.S. Navy can keep it open, if need be. What's more, the Iranians might be deterred by the fear that a skirmish over the strait would give U.S. or Israeli leaders an excuse to attack their nuclear facilities.
The obviousness of Iran's bluster suggests its weakness. Empty threats generally show desperation, not security. And Iran's weakness is not confined to water. Though Iran is more populous and wealthier than most of its neighbors, its military isn't equipped for conquest. Like other militaries in its region, Iran's suffers from coup-proofing, the practice of designing a military more to prevent coups than to fight rival states. Economic problems and limited weapons-import options have also undermined it ability to modernize its military, while its rivals buy American arms. Here's how Eugene Gholz and Daryl Press summarize Iran's conventional military capability:
Iran...lacks the equipment and training for major offensive ground operations. Its land forces, comprising two separate armies (the Artesh and the Islamic Revolutionary Guard Corps), are structured to prevent coups and to wage irregular warfare, not to conquer neighbors. Tehran's air force is antiquated, and its navy is suited for harassment missions, not large amphibious operations across the Gulf. Furthermore, a successful invasion is not enough to monopolize a neighbor's oil resources; a protracted occupation would be required. But the idea of a sustainable and protracted Persian Shi'a occupation of any Gulf Arab society--even a Shi'a-majority one like Bahrain--is far-fetched.
Despite Iran's weakness, most U.S. political rhetoric--and more importantly, most U.S. policy--treats it as a potential regional hegemon that imperils U.S. interests. Pundits eager to bash the president for belatedly allowing U.S. troops to leave Iraq say it will facilitate Iran's regional dominance. The secretary of defense, who says the war in Iraq was worth fighting, wants to station 40,000 troops in the region to keep Iran from meddling there. Even opponents of bombing Iran to prevent it from building nuclear weapons regularly opine on how to "contain" it, as if that required great effort.
Some will object to this characterization of Iran's capabilities, claiming that asymmetric threats--missiles, the ability to harass shipping and nasty friends on retainer in nearby states--let it punch above its military weight. But from the American perspective--a far-off power with a few discrete interests in the region--these are complications, not major problems. Our self-induced ignorance about Iran's limited military capabilities obscures the fact that we can defend those interests against even a nuclear Iran at far lower cost than we now expend. We could do so from the sea.