Since the war went on for eight years, each side adapted. Iraq exported oil by tanker trucks and through pipelines through Turkey and Syria.
Iran moved oil export facilities further south to escape Iraqi planes and even looked at building facilities outside the Gulf shores.
Saudi Arabia and Kuwait pondered expanding oil pipelines to the Red Sea to avoid the Gulf fighting.
Apparently, more than two decades after that war, not much was done to escape the choke point of the Strait of Hormuz in Iran's shadow, because Iran's threats to close Hormuz rattle oil markets.
Until we promise to keep the oil flowing and the Saudis promise to make up for the loss of Gulf exports:
Oil prices fell on Wednesday, after Saudi Arabia said it will offset any loss of oil from a threatened Iranian blockade of a crucial tanker route in the Middle East.
The U.S. Navy warned that any disruption of traffic through the vital Strait of Hormuz "will not be tolerated."
The route for this reserve capacity was not given, the article says. I assume some could flow through pipelines that bypass Hormuz. But I assume most of the replacement oil would only replace Iran's output. For Iraq, Kuwait, and other Gulf sources of oil to reach the world, they'll have to go through Hormuz.
This alone should let you know that Iran couldn't stop oil traffic through the Strait of Hormuz for long. If the Saudis and other producers who rely on tankers going through Hormuz were really worried that America couldn't stop Iran from blockading the strait, they'd have built those pipelines long ago.
Indeed, Saudi Arabia and the other Gulf producers might prefer to have the oil export routes "exposed" in Hormuz in order to keep American involved in the Gulf to oppose Iran generally so we can keep the oil flowing.
And we may prefer that theoretical vulnerability in order to persuade Saudi Arabia to buy American weapons, which tends to bind the Saudis to us in order to keep the weapons in working order.
If Iran ever grows powerful enough to actually close the Strait of Hormuz and hold it shut, pipelines will sprout across Saudi Arabia heading to the Red Sea and Arabian Sea.
Of course, that's why Iran courts Eritrea at the southern outlet from the Red Sea and how pro-Iranian elements in Gaza and Lebanon could help out at the northern end of the Red Sea outlet. And why Iran exercises their navy outside the Gulf.
So far, I remain confident we'd crush Iran's efforts to stop the oil flow.
UPDATE: Ah, interesting:
Normally, some 16 million barrels of oil pass through the strait daily.
However, by March, Arab exporters will be using pipelines connecting them with the Arabian Sea through the emirate of Fujairah, bypassing Hormuz. Because the strait is the only route for its oil exports, Iran could end up the principal loser.
I wonder how much it will carry? Also:
Tehran’s hopes of provoking global shortages may be exaggerated. World oil stockpiles, now at the highest ever, could be released to prevent sharp price rises. Also, Russia, Norway and Angola have plans for more production in 2012.
We're about as ready as we can be to face Iran's oil weapon.
UPDATE: There are some pipelines out there, apparently unused while Hormuz is open. In addition to the new pipeline, if I'm reading this right (on page 20), pipelines could handle about half of the traffic that normally goes through Hormuz. That would require reopening some that probably aren't reopening any time soon. But those are smaller capacity lines.
So at best, we'd need to protect 7 tankers going in and 7 going out each day to have no impact at all from Iranian threats. In the short run, releases from national and private oil reserves would cushion the impact. Not that oil prices won't spike. But eventually they would drop down somewhat.
UPDATE: More on price spikes, oil reserves, and alternative pipelines. Also, while it is true that it would be stupid for Iran to close the Strait of Hormuz because they and their ally China rely on oil from there, accidents happen. And sometimes people do stupid things.
Note, too, that the "oil platforms" we attacked in clashes with Iran were not production platforms but were bases being used by Iranian forces. In 1987, in retaliation for an Iranian strike on a tanker in Kuwaiti waters, we carried out Operation Nimble Archer on October 19, 1987, destroying three platform bases. After the mining incident the article mentions, in April 1988, we carried out Operation Praying Mantis:
At the same time that Iran was losing on the ground, Iran's navy sailed on its death ride. The naval battle was prompted by the mining of U.S.S. Samuel B. Roberts on April 14, 1988 in the first mine incident since November 1987. Five days later, America responded with Operation Praying Mantis. Designed as a proportional response to the damaged U.S. frigate, the operation involved the destruction of two Iranian oil platform bases. The Sassan platform was demolished by a Marine landing team while the Sirri platform was destroyed by naval gunfire. During this operation, an Iranian patrol boat was sunk and F-4 Phantom fighter bombers were driven off by American surface to air missile fire. Iran's response set off a chain of events that left perhaps three of her patrol boats at the bottom of the Gulf and two modern frigates smashed. American forces dodged more Iranian attacks including the impressive evasion of five Silkworms by Jack Williams. The Only American loss, a Sea Cobra attack helicopter, was lost by accident and not hostile action.
[From a long "post" that summarizes an unpublished manuscript of the Iran-Iraq War.]