U.S. Sen. Marco Rubio arrives for the Senate Republican leadership elections at the U.S. Capitol on Nov. 13 in Washington, DC. Just how Mr. Rubio will be able to square his principles with Donald Trump’s 'America First' credo now that he has been named secretary of state remains a mystery to most members of the Blob.Kevin Dietsch/Getty Images

The bad blood between Donald Trump and Marco Rubio, who ran against each other for the 2016 Republican presidential nomination, went far deeper than the jibes they exchanged during the race about the size, or lack thereof, of each other’s physical attributes.

Mr. Rubio, then still a first-term Florida senator, had emerged as one of his party’s most notorious foreign policy hawks. And he pounced on his GOP rival’s ignorance after a radio interview in which Mr. Trump had been unable to identify the heads of Iran’s Quds force, Hamas or Hezbollah, and confused the Quds with Kurds.

“If you don’t know the answer to these questions, then you are not able to serve as commander-in-chief,” Mr. Rubio charged after Mr. Trump’s interview. “National security is the most important obligation of the federal government. If you are going to be a presidential candidate, you need to take this seriously.”

Even in Washington, few........

© The Globe and Mail