Despite his own isolationist musings, the first choices of President-elect Donald Trump’s new administration come from a decidedly more traditionalist wing of the Republican Party.

On Tuesday, Trump formally announced that Rep. Michael Waltz, R-Fla., would become his national security adviser. Sources have said Trump plans to tap Sen. Marco Rubio, R-Fla., as secretary of state.

Together with New York representative Elise Stefanik – set for the role of ambassador to the United Nations – the trio is expected to advance a staunchly pro-Israel agenda.

Ukrainian advocates are also somewhat relieved.

“Kiev is looking at these agreements with some relief – they clearly know there is room for engagement,” a source familiar with the Ukrainian operations told Fox News Digital. They added that after a Biden administration that they said was overly fearful of escalating U.S. involvement in the war with Russia, “a not insignificant number of senior Ukrainian officials are cautiously optimistic about what a change of pace might look like.”

Waltz, who once served as a counterterrorism adviser to former Vice President Dick Cheney, is widely considered a hawk on China and Iran. He vociferously opposed President Joe Biden’s withdrawal from Afghanistan.

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“What no one can ever do for me, including this administration right now, is create a counterterrorism plan that is realistic without us there,” Waltz said in an interview a few days after the withdrawal.

The former Army Green Beret officer and ex-defense company CEO introduced legislation during the first Trump administration that would have prevented a massive troop withdrawal in Afghanistan unless the director of national intelligence declared that the Taliban would not associate with Al-Qaeda.

On Tuesday, Trump formally announced that Rep. Michael Waltz, R-Fla., would become his national security adviser. (John Nacion/Getty Images)

“I think we’re in for a long haul and I think our nation’s leaders need to start saying to the American people, ‘I’m sorry. We have no choice. We have been working on what will happen for fifteen years. a war between multiple generations, because we’re talking about defeating an idea,” Waltz said on Afghanistan at the 2017 Conservative Political Action Conference.

Waltz voted to keep authorization for the 2021 Iraq war on the books and voted against ending U.S. support for the Saudi war in Yemen.

In an interview with NPR last week, Waltz said the war between Russia and Ukraine could end if the US exerts some influence.

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Russia’s “war machine will dry up very quickly” with U.S. economic sanctions, Waltz said, and “by removing the handcuffs on the long-range weapons we delivered to Ukraine.” Biden has long refused to allow Ukraine to use American weapons to attack deep into Russia.

When Israel counterattacked Iran’s military targets last month, Waltz complained that it had not gone after Iran’s oil and nuclear facilities. “Has Biden/Harris once again pressured Israel to do less than it should?” he asked.

Rubio is now a known hawk in China, Iran and Venezuela, where he has worked to dethrone dictator Nicolas Maduro.

Rubio once supported U.S. aid to Ukraine, but when the issue was raised again earlier this year, he was one of 15 Republicans who voted against an additional funding package, citing insufficient border provisions.

Sources have told Fox News that Trump plans to tap Sen. Marco Rubio, R-Fla., as secretary of state. (Joe Raedle/Getty Images)

He is a strong supporter of American support for Taiwan. When Trump expressed concerns about U.S. support for Taiwan and suggested the island should pay the U.S. for its defense, Rubio predicted that Trump would “continue to support Taiwan” if he wins back the White House.

Like Trump, both Waltz and Rubio have criticized NATO allies for not spending enough on defense. Rubio has insisted that Europe must “take the lead” in his defense: “Germany, France and the United Kingdom are more than capable of managing their relationship with the nuclear-armed warring parties in the east. But they will never take over responsibility for that long. because they can rely on America.”

Rubio last year co-sponsored legislation that would prevent any president from withdrawing the U.S. from NATO without congressional approval, a measure seen as a precaution if Trump wins the presidency and his frequent threats to collapse the alliance would continue to give.

His choice sparked some backlash from some Trump die-hards who view him as too aggressive.

Together with Elise Stefanik, the new UN ambassador, Waltz and Rubio are expected to advance a staunchly pro-Israel agenda. (Adam Gray/Bloomberg via Getty Images)

“Apparently there hasn’t been an SOS choice yet FYSA (for your situational awareness),” Rep. Anna Paulina Luna (R-Fla.) posted late Monday on X, after news outlets began reporting that Trump had settled for Rubio.

Libertarian-minded comedian Dave Smith said Tuesday that Rubio is “a disaster.”

“You might as well give Liz Cheney the State Department,” Smith wrote. “Terrible sign.”

Stephen Wertheim, a senior fellow at the Carnegie Endowment for International Peace, said Waltz and Rubio “above all signal a hard line toward China, not just economically, but across the board – in political, military and ideological competition .”

“These choices leave me wondering whether Trump will deliver on his sometimes reluctant foreign policy promises, including his stated desire to end the war in Ukraine sooner rather than later and see Israel conclude its wars,” he said . “I get flashbacks to the first Trump administration.”

But, he added, “Rubio is no longer quite the Rubio many remember from 2016.”

“Rubio appears to understand that the United States faces limited resources and must set strategic priorities in an increasingly competitive world.”

And some reluctant thinkers harbor cautious optimism.

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“If (Rubio) channels Trump’s approach instead of pursuing his own agenda, he could redefine the role of the State Department in a way that is both respected and effective abroad. Rubio knows his future prospects are tied to his ability to implement Trump’s policies, not personal ambitions,” said Jason Beardsley, senior coalition advisor for Concerned Veterans for America.

“Having worked closely with Waltz, I can vouch for his deep understanding of America’s strategic priorities. He is passionate about reforming the Department of Defense from within and ensuring national security without overburdening our military with costly, unnecessary fighting.”