Donald Trump travels to the U.N. on Tuesday to address the General Assembly.  His speech will touch familiar themes, including condemnation of North Korea, Iran, and perhaps even Russia.  He will also try to reassure delegates that he believes in an international system but will criticize the U.N. for its timidity on North Korea and its mismanagement and almost certainly urge other countries to do more to fund the organization.  The U.S. is currently responsible for about 60% of U.N. funding, and Trump will lecture the delegates about failing to pay their fair share.

In short, there will probably not be anything too surprising in Trump's speech.  But he might want to thank U.N. ambassador Nikki Haley for boosting U.S. interests so effectively at the world body.  Haley's plainspoken, sometimes blunt rhetoric has been a refreshing change from the mealy-mouthed utterings of her predecessor, Samantha Power.

Reuters:

Twice in five weeks she persuaded the 15-member U.N. Security Council to unanimously boost sanctions on North Korea. Her blunt language has raised eyebrows among diplomats.

At the same time she has been careful not to steal the limelight from Trump, a wealthy businessman and former reality television star.

"I personally think he slaps the right people, he hugs the right people, and he comes out with the U.S. being very strong in the end," Haley told White House reporters on Friday.

European Council on Foreign Relations U.N. expert Richard Gowan said Haley's success could make Trump nervous and that it would be a "bad deal for her" if she was asked to replace Tillerson as secretary of state.

"She would lose the independence she enjoys in New York and (it would) tie her more closely to the president's agenda. But it is an offer that she could not refuse. It's an irony that the one way Trump can hurt Haley is to promote her," he said.

Haley credits Trump with any U.S. achievements at the United Nations. After the Security Council toughened sanctions on North Korea this month, she praised his "strong relationship" with his Chinese counterpart for the result.

When he dismissed the Sept. 11 U.N. resolution, which had been weakened by China and Russia, as "just another very small step, not a big deal," Haley jumped to his defense and dismissed any suggestion they were not on the same page.

"If we have to go further, this is going to look small compared to what we do," she said at the time.

Haley has made her mark also by fighting what she describes as U.N. anti-Israel bias, pushing for U.N. reform amid Trump's call to slash U.S. funding, accusing Iran of meddling in the Middle East and challenging Russia over Ukraine and its support for Syrian President Bashar al-Assad.

A senior administration official, speaking on condition of anonymity, said that during a National Security Council meeting on Iran this month, Trump specifically asked Haley's opinion about what strategy to pursue.

"She gave her opinion, and he liked her point of view," the official said. "She wasn't afraid to speak up."

Haley must be careful not to get too far out ahead of the president.  Donald Trump is not the kind of man who will sit still for being upstaged.  In fact, recent positive press about Haley might lead to some tension between the two.

But Haley appears to have a strong rapport with the president, and they look as though they're on the same page when it comes to vital issues facing U.S. foreign policy.  That relationship has translated into effective leadership at the U.N. by Haley.

Talk of Haley running for president is premature.  But you can bet that if the opportunity to run presented itself, she would be reluctant to turn it down.