It begins: unprecedented tit-for-tat formal "terror" designations exchanged between Washington and Tehran on Monday could soon enter a hot war on the ground. A mere hours after President Trump formally designated Iran's Islamic Revolutionary Guards Corps (IRGC) as a terrorist organization on Monday, Iran's foreign ministry responded in kind by immediately putting forward a bill placing the US Central Command (CENTCOM) on a list of organizations designated as terrorists, akin to ISIS.
This means each side has given its armed forces authorization to target the other as part of "war on terror" operations. And already on Tuesday an IRGC commander has put the US Navy in the Persian Gulf on notice, warning it not to come anywhere near Revolutionary Guards speed boats. Specifically, according to Iran's ISNA news agency, Tehran has warned that America's aircraft carrier currently deployed to the gulf, the USS John C. Stennis, should not come anywhere near IRGC boats.
According to Reuters, citing Iranian state media:
An Iranian Revolutionary Guard commander warned the U.S. Navy to keep its warships at a distance from Revolutionary Guards speed boats in Gulf waters, a day after the United States designated the Guards as a terrorist organisation.
“Mr Trump, tell your warships not to pass near the Revolutionary Guards boats,” ISNA news agency reported a tweet from Mohsen Rezaei as saying.
Over the past years there's been a number of intercept incidents in the Persian Gulf carried out by each side — none of them escalating to the point of serious exchange of fire.
The last major international incident was the January 2016 crisis wherein two US Navy Riverine Command boats cruising from Kuwait to Bahrain strayed into Iranian territorial waters, resulting in the combined of crew of nine men and one woman being taken into Iranian detention. The crew was released 15 hours later, but to the great embarrassment of Washington, for which four of the sailors were later punished.
In total the IRGC actually has millions of members, while the more elite "foreign and clandestine" arm, the Quds force, is estimated to be at anywhere between 10,000 and 20,000 members. The Quds Force is known to report directly to the Supreme Leader of Iran, Ayatollah Khamenei.
Further on Tuesday, the IRGC stated that US pressures based on the latest official terror designation will only "increase the Guards' defense and offensive power," according to state media.
All of this turns the Persian Gulf area into a huge potential flash point for a major incident, especially considering Iranian military commanders have over the past year repeatedly threatened to close the vital Strait of Hormuz water way in the gulf, a key strategic oil transit point.