A surge of tensions in the Gulf has shown the risk of a military confrontation between arch-foes Iran and the United States, even if any conflict would likely be marked by guerrilla warfare rather than full-scale battles, analysts say.
A series of mysterious attacks on ships off the coast of the United Arab Emirates, the key ally of Tehran's Gulf rival Saudi Arabia, prompted President Donald Trump to warn Iran would "suffer greatly" if it harmed US interests.
The United States and Iran have had no diplomatic relations since the seizure by Iranian radicals of American embassy staff in the wake of the 1979 Islamic revolution.
The two sides have at times been close to conflict — in particular during a tense period under former US president George W. Bush — but analysts see a series of factors as making the current moment particularly combustible.
Trump dismayed European allies by pulling out of the 2015 deal on Iran's nuclear programme unilaterally and is now ratcheting up the rhetoric against Tehran. Iran and Saudi Arabia, a close ally of the United States for decades, are both enmeshed on opposing sides in the conflict in Yemen. And in US ally Israel, which Iran refuses to recognise, Prime Minister Benjamin Netanyahu is pushing for a hard line against Iran.
"The Trump administration has significantly increased tensions in the region and has therefore increased the odds of some sort of inadvertent or even deliberate military clash with Iran," said International
Crisis Group (ICG) Iran project director Ali Vaez. "The odds of a clash occurring, even without provocation, are quite high." he told AFP.