Such a steep spike in crude oil prices would plunge the United States and Europe back into recession, said Money Morning Global Energy Strategist Dr. Kent Moors.
Iran just concluded a 10-day military exercise intended to prove to the West that it can choke off the flow of Persian Gulf oil whenever it wants.
The world's fourth-biggest oil producer is unhappy with fresh U.S. financial sanctions that will make it harder to sell its oil, which accounts for half of the government's revenue.
"Tehran is making a renewed political point here. The message is - we can close this anytime we want to," said Moors, who has studied Iran for more than a decade. "The oil markets are essentially ignoring the likelihood at the moment, but any increase in tensions will increase risk assessment and thereby pricing."
One reason the markets haven't reacted much to Iran's latest rhetoric is that although it has threatened to close the Strait of Hormuz many times over the past 20 years, it has never followed through on the threat.
But a fresh wave of Western sanctions could hurt Iran's economy enough to make Tehran much less cautious.
The latest sanctions, signed into law by U.S. President Barack Obama on Saturday, will make it far more difficult for refiners to buy crude oil from Iran. And looming on the horizon is further action by the European Union (EU), which next month will consider an embargo of Iranian oil.
"The present United Nations, U.S. and EU sanctions have already had a significant toll," said Moors. "They have effectively prevented Iranian access to main international banking networks. Iran now has to use inefficient exchange mechanisms."
Because international oil trade is conducted in U.S. dollars, Moors said, Iran must have a convenient way to convert U.S. dollars into its home currency or other currencies it needs, such as euros.
Pushed to the BrinkThe impact of the sanctions combined with internal political instability has driven Iran to turn up the volume on its rhetoric.
"Tehran has limited options remaining," Moors said, noting Iran has historically used verbal attacks on the West to distract its population from the country's problems. "The Iranian economy is seriously weakening, the political division among the ayatollahs is increasing, and unrest is rising."
Analysts worry an Iranian government that feels cornered would be more prone to dangerous risk-taking in its dealings with the West. So while totally shutting down the Strait of Hormuz isn't likely, Iran could still escalate a confrontation beyond mere talk.