He's the 2nd top Trump White House official to either resign or be fired in the past week -- following in the ignominious footsteps of top Trump economic adviser Gary Cohn . And Cohn's departure followed hard on the resignations of White House communications director Hope Hicks and Josh Raffel, a confidante of Jared Kushner and Ivanka Trump. Plus, Trump body man John McEntee was fired on Monday due to ongoing security clearance issues. And so was Steve Goldstein, the Under Secretary of Public Affairs at the State Department, who out out a statement Tuesday morning saying Tillerson was unaware of the reason he had been fired.

The prevailing question now is: Who's next?

There's any number of options, given that Trump has actively feuded with lots of his Cabinet since hand-picking them just over a year ago. Below, I've ranked a variety of embattled Trump Cabinet members based on their likelihood to be given the Rex treatment -- aka fired via Twitter.

1. Jeff Sessions: Trump has publicly attack the attorney general repeatedly -- calling him, among other things, "beleaguered" and "DISGRACEFUL." He has told not one but two news organizations that he would not have appointed Sessions as AG if he knew Sessions would recuse himself in the Russia investigation. He refers to Sessions as "Mr. Magoo" in private settings, : Trump has publicly attack the attorney general repeatedly -- calling him, among other things, "beleaguered" and "DISGRACEFUL." He has told not one but two news organizations that he would not have appointed Sessions as AG if he knew Sessions would recuse himself in the Russia investigation. He refers to Sessions as "Mr. Magoo" in private settings, according to the Washington Post . I mean....

2. Jeff Sessions: See #1.

4. H.R. McMaster: Rumors of : Rumors of tension between the National Security Adviser and Trump have been rampant for months. There's even been chatter about how to move McMaster back into the military in order to get him out of the White House. With Trump jettisoning Tillerson, might he move on another member of the more globally-minded wing of his foreign policy team?

7. Ben Carson: The Housing and Urban Development secretary purchased -- and then canceled -- : The Housing and Urban Development secretary purchased -- and then canceled -- a $31,000 dining set for his work office . Why isn't he higher on this list? Because Trump likes him -- and the two went through the political wars together in 2016. I think that counts for something -- maybe a lot -- in Trump's book.

8. John Kelly: Reports are rampant that Kelly and Trump have fallen out, and that, as importantly, the White House chief of staff is in semi-open warfare with Javanka. : Reports are rampant that Kelly and Trump have fallen out, and that, as importantly, the White House chief of staff is in semi-open warfare with Javanka. Kelly's ham-handed handling of the Rob Porter debacle and the resultant news coverage clearly knocked him down several pegs in Trump's eyes. And, Kelly was reportedly part of a "suicide pact" with Tillerson and Defense Secretary Jim Mattis -- that if one left or was fired, they would all leave. Working against the idea of Kelly being fired: Trump loves "his" generals.

9. Betsy DeVos: The Education secretary has had a very rocky road. This weekend was the bumpiest bit yet as DeVos seemed totally out of her depth in an interview with "60 Minutes" Lesley Stahl. Trump hates negative headlines that he doesn't cause. But, it seems like he has more urgent firing priorities than DeVos.

10. Jim Mattis: The "Mad Dog" is only on this list because of the aforementioned "suicide pact" with Tillerson and Kelly. That aside, he appears to be the Cabinet secretary who has clashed the least -- or the least publicly -- with Trump.