CNN  — 

At a lunch at the White House on Monday with more than a dozen UN ambassadors, President Trump poked some fun at his own UN Ambassador Nikki Haley.

“Does everybody like Nikki?” Trump asked the assembled ambassadors as Haley sat by his side. Amid laughter Trump added: “Otherwise, she can easily be replaced.”

Cue awkward laughter.

Now, Trump was joking. And everyone in the room – including Haley – understood that. But, that doesn’t mean he was entirely kidding.

Two things we know about Trump suggest that beneath his attempt at humor was a hard-edged point.

First, we know he likes to keep the people working for him on their toes. Never being absolutely certain where you stand in the Trump orbit is one of his tried and true management techniques. He plays favorites, pits people against one another and listens to different people on different days without any seeming rhyme or reason.

Witness White House chief strategist Steve Bannon’s arc since he came to Washington. Bannon seemed to be Trump’s closest and most trusted adviser in the earlier days of the administration – pushing Trump successfully on the travel ban and ramping up talk of the “deconstruction of the administrative state.” But then Bannon fell into disfavor, with Trump offering a public condemnation of Bannon as “a guy who works for me.”

This “joke” about Haley certainly seems to be in keeping with Trump’s long-standing practice of keeping his people guessing.

Second, we know that Trump doesn’t like when people around him start getting too much positive attention. And, Haley fits that description perfectly. She’s largely won positive reviews in her role, particularly for an impassioned speech she gave at the United Nations following the gassing of civilians by Syrian President Bashar al-Assad.

Haley is, without question, the early star of the Trump administration. Heck, there are already rumors about Haley as a future presidential candidate herself!

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That does not sit well with Trump, who doesn’t share the spotlight well or easily. So, when given the chance to take Haley down a peg via a “joke,” you can be damn sure Trump was going to take it.

The saying goes “a joke is truth wrapped in a smile.” That’s just what happened with Trump and Haley on Monday.