Despite attempts to deescalate the situation, new sanctions targeting Ayatollah Ali Khamenei may be viewed as highly provocative by his millions of followers in this region.
He is a religious figure and his Shia faithful could see this as an insult that demands a response.
Following on from its abandonment of the 2015 nuclear deal with Iran, Washington’s latest move puts relations further back than square one.
Now the Americans and Iranians appear even more entrenched – the hardest hitting sanctions ever will surely see the Iranians re-start their nuclear programme in earnest.
At a news conference following President Trump’s announcement, his Treasury Secretary Steve Mnuchin appeared to suggest that the sanctions would extend to the Iranian Foreign Minister later this week.
Javad Zarif is Iran’s top diplomat, and his designation would surely make even more remote any possibility of the two sides negotiating their way out of this crisis.