"He who can destroy a thing, controls a thing."
- Paul "Muad'Dib" Atreides (Obligatory Dune reference)
Lately I've read lots of articles on the escalating tension between the US and Iran, but remarkably few commentators have drawn attention to Iran's ability to cripple global oil trade. It would be trivial for them to mine the narrow Straits of Hormuz. Around 20% of all traded oil and some 35% of all seaborne oil shipments pass through the straits aboard enormous, highly vulnerable tankers. Even if Iran's military capabilities were miraculously nullified and the mines somehow cleared, the cost of insuring the tankers would skyrocket, driving up oil prices globally.
Iran could also use its long-range missiles and/or other methods to destroy major oil refineries and vital desalination plants on the Arabian peninsula, with ensuing chaos and shortages.
Even if the US were not still dependent on oil from the Middle East, all its major allies and trading partners are. The global economy needs a steady flow of oil from the Middle East, and the US economy is dependent on the global economy. War with Iran is madness any which way you look at it. The spines on this hedgehog are too sharp.