This seems to be a pretty clear warning of consequences for Iran:
[CIA Director Mike] Pompeo, who has voiced staunch opposition to Iran, said he sent the letter to Gen. Qassem Soleimani, a leader of Iran's Islamic Revolutionary Guard Corps and elite Quds Force, but the general didn't read it.
"I sent a note. I sent it because he had indicated that forces under his control might in fact threaten U.S. interests in Iraq," Pompeo said at a defense forum at the Ronald Reagan Presidential Foundation and Institute in Simi Valley, California. "He refused to open the letter — didn't break my heart to be honest with you."
"What we were communicating to him in that letter was that we will hold he and Iran accountable ... and we wanted to make sure that he and the leadership of Iran understood that in a way that was crystal clear."
That's good. There is a reason Iran was named as a founding member of the Axis of Evil and a reason why making the Iran nuclear deal with them was a massive mistake.
We should sink Pasdaran (Revolutionary Guards) military assets if we have to enforce that red line.
