North Korean diplomats have a front-row seat as U.S. President Donald Trump gives his first UN speech on Tuesday, addressing a world body he once belittled as "just a club for people to get together, talk and have a good time."

Well, Mr. Trump — welcome to the club.

America's troubles with Pyongyang should top the diplomatic agenda after the hermit kingdom tested a thermonuclear bomb and several missiles in recent weeks. Trump is also expected to address threats to exit the 2015 Iran nuclear deal, and could be challenged by fellow leaders regarding U.S. withdrawal from the Paris climate accord.

World leaders in the audience will hear some familiar campaign motifs. The White House said there will be an emphasis on "America First," isolationist-sounding rhetoric that might have helped him win the presidency, but which might unsettle nations more receptive to global governance.

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UN Secretary General Antonio Guterres, left, listens as U.S. President Donald Trump speaks during a session on reforming the UN in New York on Monday. (Lucas Jackson/Reuters)

U.S. Ambassador to the UN Nikki Haley offered a preview of the president's address, saying: "He slaps the right people, he hugs the right people, and he comes out with [the] U.S. being very strong in the end."

Trump is expected to speak at about 10:30 a.m. ET. Here's what to watch for:

Will he bash the UN again?

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Inside the United Nations General Assembly in 2014 in New York City. (Andrew Burton/Getty)

Trump has slammed the organization for years. But now he may have to depend on the value of diplomatic partnerships to help slow North Korea's rapidly advancing nuclear weapons program, says UN expert Richard Gowan.

"It's ironic because Trump came into office blasting the UN," he said. "The fact is although he's an anti-multilateral president, the only way that he can avoid escalating the Korean situation is to hope that the Security Council will continue to back U.S. efforts" to clamp down on the North via economic sanctions.

Trump is relying on the UN Security Council to manage a problem that "could culminate in a nuclear conflict threatening U.S. cities," Gowan says.

The president has called for the slashing of U.S. financial contributions. Of the 193 UN member nations, the U.S. tops the list of donors and Trump has criticized the organization for bureaucratic bloat. It's notable that the opening day of the annual UN General Assembly (UNGA) session on Monday was dedicated to a U.S.-led push for "meaningful reform," a political declaration that drew more than 120 signatories.

How will 'America First' play to this crowd?

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U.S. Ambassador to the UN Nikki Haley, left, and U.S. President Donald Trump participate in a session on reforming the United Nations at UN headquarters in New York on Monday. (Kevin Lamarque/Reuters)

"Not particularly well," says Clifford May, president of the conservative-leaning Foundation for Defense of Democracies in Washington, D.C.

May, who has been critical of the UN, expects Trump to frame "America First" in the context of sovereignty, with the United States not being beholden to any "parliament of nations with supreme authority" on international laws.

Trump is viewed as an isolationist. A head of state whose presidential platform was largely defined by building walls will need to articulate his vision for global leadership and co-operation on matters of mutual concern.

Asked by reporters on Monday about what will drive the U.S. agenda at the UNGA, Trump summed up his priorities with a spin on his "Make America Great Again" slogan. In what appeared to be a slight dig at the organization, Trump said his goal is to "make the United Nations great," period. "Not," he stressed, to make it great "again."

Trump said the organization has yet to have "reached its full potential."

Could the U.S. cede its leadership?

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Chinese Foreign Minister Wang Yi takes part in a meeting of the UN Security Council in 2016. As the U.S. raises concerns among world leaders that it's moving towards isolationism, experts warn a leadership vacuum is being created that could allow a nation like China to assume a leadership role. (Lucas Jackson/Reuters)

America's presence this year will be diminished, a "symbolic display of disinterest" towards the UN, Gowan says.

According to Politico, more than 1,000 U.S. government officials usually attend UNGA. That figure will reportedly shrink by the hundreds.

"Fewer U.S. officials at side meetings, fewer American officials on hand to spin whatever Americans say to their foreign counterparts," Gowan says. "It will have a slight effect on the mood of the General Assembly as a whole, feeding into a narrative about U.S. disengagement."

Secretary of State Rex Tillerson reportedly told aides the U.S. goal is to make a "toe-print, not a footprint" at the summit.

UN Secretary General Antonio Guterres has warned the U.S. that disengagement from the UN stage could create a leadership vacuum. Analysts note that foreign adversaries such as China might step in and start carrying more weight in discussions if the U.S. withdraws from more international policy decisions.

"It will be unavoidable that other actors will occupy that space," Guterres said at a June news conference. "And I don't think this is good for the United States, and I don't think this is good for the world."

How will North Korea's delegation react?

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The North Korean delegation, including Foreign Affairs Minister Ri Yong Ho, will have a front-row seat this year when U.S. President Donald Trump is expected to make a speech condemning the rogue nation. (Timothy A. Clary/AFP/Getty Images)

By way of the UNGA seating lottery, North Korea's delegation will have a front-row view of the leader of their arch-enemy the United States, an arrangement that would appear to set up some high-level drama.

Trump will almost certainly condemn Pyongyang for its nuclear tests and threats against the U.S. and its treaty allies. He will likely reiterate the need to put maximum diplomatic pressure on the North.

With North Korea in the front row, Gowan said, "the possibility is they just won't turn up, or they'll walk out.

"But I suspect they might just sit there and glower."

That would be in keeping with the North's usual conduct during speeches, said Lisa Collins, an expert on North Korea with the Center for Strategic and International Studies, a non-partisan Washington think-tank.

"Usually, they're pretty good about following diplomatic etiquette when it comes to when people are delivering speeches," she said.

Collins expects the delegation to hold its own press briefings to counteract what Trump might say, or accuse the U.S. of threatening the North and deepening tensions.

Could Trump become this year's sideshow?

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Former Libyan leader Moammar Gadhafi addresses the 64th UN General Assembly at the UN headquarters in 2009. His speech lasted nearly 100 minutes. (Mike Segar/Reuters)

To a great extent, the U.S. president is the main event, but it's hard to predict when he'll decide to go off message. World leaders will be watching for incendiary remarks that stray from his speech, analysts say.

The late Libyan leader Moammar Gadhafi was known for delivering a screed that clocked in at 96 minutes long in 2009. On the same stage, Venezuela's late leader Hugo Chavez once called former U.S. president George W. Bush "the devil" in a 2006 diatribe. In 1960, Cuba's Fidel Castro spoke for 269 minutes.

Gowan's sense is that although some expect Trump will "go off on some long, rambling speech like Gadhafi or Castro," the president will show more discipline, both for good press and to deny naysayers.

That may well be the case, said May of the Foundation for Defense of Democracies.

"But look, Trump's an impulsive guy," he said. "Will there be controversy over what he has to say? I guarantee it, whether he stays on script or not."

Trump is speaking live at 10 a.m. ET.  You can watch live online at CBC.ca, on the CBC News Facebook page or on our YouTube channel.  You can also watch our live television coverage on CBC News Network.