The U.S. is expected to designate Iran's Revolutionary Guard Corps a terrorist organization, perhaps as early this week.  The move is part of the Trump administration's increasingly aggressive posture toward the Iranian regime that include sanctions on the leadership and the country's energy sector.

The Revolutionary Guards are a key component of both the regime's foreign policy and domestic oppression.  They are under the direct command of Supreme Leader Ayatollah Khamenei.  The Guards have been active in Syria, working side by side with the Lebanese terrorist group Hezb'allah.

CNN:

Defense officials have told CNN that US troops in Syria and Iraq often find themselves operating in close proximity to members of the IRGC.

Last year, CNN reported that Director of National Intelligence Dan Coats cautioned the administration that designating the IRGC could pose dangers to US forces, according to one source familiar with the matter.

"Under the cover of the Syrian war, the IRGC is now trying to plant military roots in Syria and establish a new strategic base to threaten Syria's neighbors such as Israel," Brian Hook, the State Department's special representative for Iran, told reporters Tuesday.

During the Obama administration, the Guards acted with impunity, killing hundreds of American soldiers.

"In Iraq, I can announce today, based on declassified US military reports, that Iran is responsible for the deaths of at least 608 American service members.  This accounts for 17 percent of all deaths of US personnel in Iraq from 2003 to 2011.  This death toll is in addition to the many thousands of Iraqis killed by the IRGC's proxies," he added.

Several individual Guard commanders are already under sanction.  That's because the Guards not only function as a military and paramilitary outfit, but also own lucrative businesses in the telecommunications and energy industries.

But designating them a terrorist group carries with it some risk.  U.S. troops in Iraq and Syria work in close proximity to the Revolutionary Guards in our fight against ISIS.  While technically our enemies, there has been an uneasy truce for years as both the Guards and U.S. troops share a common enemy in ISIS.

This move is long overdue.  Since the early 1980s, the Quds Force of the Revolutionary Guards has operated beyond the borders of Iran, murdering dissidents and assisting Hezb'allah in carrying out terrorist attacks.  Naming them a terrorist organization will not materially affect their ability to operate outside Iran, but it ratchets up the pressure on Iran by a few notches.