The ambassador to the UN better watch her back, particularly with Rex Tillerson trying to get control over her public remarks. Photo: Bryan R. Smith/AFP/Getty Images

Without question, one of the stars of the first 100 days of the Trump presidency has been ambassador to the UN and former South Carolina governor Nikki Haley. Even as other members of the administration seemed to stumble and mumble and struggle to get a grip on their new responsibilities, Haley made news with ringing pronouncements that typically pleased foreign-policy elites fearful that Trump would upset long-established policies. Early on, she made waves by attacking Russia for its occupation of the Crimea, an act that had almost entirely escaped any negative attention from the president. More recently, she publicly conceded Russia was “certainly” involved in the U.S. elections of 2016, an obviously perilous line of thinking for the boss.

But Haley probably got her biggest props over Syria, where she seemed at times to be well out in front not only of Trump but of the ostensible architect of the administration’s foreign policy, Secretary of State Rex Tillerson, as Abigail Tracy noted:

Part of the Trump foreign-policy plan is that there is no plan. And, shortly after the chemical-weapons attack on a northern rebel-held province in Syria, Haley held up unsettling photos of child victims of the attack and condemned Russia as complicit. She sounded very much like her predecessor, Samantha Power, but not at all like any member of the Trump team up to that point. Then, during an interview with CNN’s State of the Union after the Trump administration ordered last week’s bombing of a Syrian airbase, the media-friendly U.N. ambassador told host Jake Tapper that Assad is “not the leader” the war-torn Middle Eastern country needs and insisted there is “not any sort of option where political solution is going to happen with Assad at the head of the regime.” Haley’s suggestion that the U.S. missile strike could be a harbinger of a regime change in Syria eclipsed Rex Tillerson’s more measured remarks, which emphasized that defeating the Islamic State remains the priority of the U.S. military in the Middle East.

Haley’s outspokenness has been all the more remarkable given her zero experience in foreign policy before getting this job, and her habit of surrounding herself with Palmetto State political advisers rather than international affairs experts. It sure looks like she’s been winging it, and so far doing it brilliantly, from the point of view of her own career trajectory (she is already appearing on post-Trump presidential lists, and at the age of 45, has a lot of time to rise and shine).

But like Icarus, she could be in danger of flying too high for her own good. According to a report from the New York Times, Tillerson is now moving to rein her in:

[I]n an apparent attempt to foster greater coherence in American foreign policy, State Department officials are urging [Haley’s] aides to ensure her public remarks are cleared by Washington first.

An email drafted by State Department diplomats urged Ms. Haley’s office to rely on “building blocks” written by the department to prepare her remarks.

Her comments should be “re-cleared with Washington if they are substantively different from the building blocks, or if they are on a high-profile issue such as Syria, Iran, Israel-Palestine, or the D.P.R.K.,” added the email, the text of which was seen by The Times. D.P.R.K. refers to the Democratic People’s Republic of Korea, or North Korea.

It is not clear whether Donald Trump himself, not known for gracefully sharing the spotlight with underlings, shares his State Department’s apparent concern that Haley is a potentially loose cannon with her own agenda. But there was an eye-raising incident at a White House dinner for ambassadors to the UN Security Council, where Haley sat next to The Boss, who said this:

“I want to thank Ambassador Nikki Haley for her outstanding leadership and for acting as my personal envoy on the Security Council. She is doing a good job. Now, does everybody like Nikki?” Trump said. “Otherwise she could be easily replaced, right? No, we won’t do that. I promise you we won’t do that. She’s doing a fantastic job.”

Maybe that was a joke, or maybe it was a supremely Trumpian way of reminding Haley that she serves at his pleasure.

She might want to watch her back.