American isolationism? World signals it may no longer be possible.

Donald Trump, presidential candidate, was going to buck seven decades of American leadership and imperial engagement with the world by turning inward and implementing an “America First” foreign policy.

Donald Trump, president of the United States, appears to be finding that the world is not ready for a withdrawn and isolationist America.

Indeed the rapid evolution of a maverick and topsy-turvy presidency to its current awkward embrace of a more traditional internationalist role suggests the world still craves the kind of stabilizing and order-producing – if certainly imperfect – leadership the US has provided since World War II.

“Trump came in promising that America would stick to its own knitting, but he’s realizing the US has a unique role to play in the world that in many ways neither the US nor the world can do without,” says Robert Lieber, a professor of government and international affairs at Georgetown University in Washington.

“It’s happening by fits and starts, and it’s still early to call it decisive,” he adds, “but the signs are pointing to a shift away” from retreat and isolationism.

For many world leaders, US leadership is important not just for stability and order, but for the defense of shared, cherished values.

So many of the world’s higher aspirations since the end of World War II – democratic governance, universally recognized human rights, more equitable prosperity and development – have their roots in an international system devised by the West and led by the US, says David Milliband, the former British foreign secretary. But it’s a system of values that would be gravely weakened by the retreat of its primary backer, he says.

“These universal values need to be defended because they are under constant threat,” says Mr. Milliband, now president and CEO of the International Rescue Committee in New York. “And clearly America needs to be at the forefront of that defense.”

Barack Obama dabbled in the notion of pulling America back – he used the West’s Libya intervention in 2011 to test-fly the idea of America “leading from behind,” for instance.

Trump’s America, on the other hand, wasn’t even going to lead, but would worry about itself first and retreat from a global role it could no longer afford.

Yet like the adolescent boy who protests but then adjusts to his first suit – maybe even secretly liking the way he feels in it – Trump is backing off his signature claims that the world is taking advantage of the US through costly security alliances and skewed trade deals.

Mounting evidence

Evidence of Trump’s adaptation and conforming to the role the world expects of America has piled up in recent weeks. Hosting NATO Secretary General Jens Stoltenberg at the White House Wednesday, the American president who as a candidate dismissed the Alliance as “obsolete” declared that NATO is “no longer obsolete” because it has adapted to take on the challenge of terrorism.

Hardly trashing the NATO alliance, Trump lauded it instead as “a bulwark of international peace and security.”

No longer is Trump alarming Japan and South Korea by suggesting they may have to get their own nuclear weapons instead of relying on the American nuclear umbrella. Now he's telling them America’s defense of the two countries in the face of a belligerent North Korea is rock solid.

And whereas Trump once promised steps to up-end the international trading system for which the US served as general contractor, his actions are much less unilateral. He did not declare China a currency manipulator as one of his first acts, just as talk of a 45 percent tariff on Chinese goods has vanished. He did not rip up NAFTA, as promised, but instead is quietly negotiating to update the 1994 trade deal regulating the North American market.

'I now have responsibility'

But it is on Syria that Trump has most abruptly boomeranged from isolationist to interventionist and practitioner of America’s traditional role defending international security and norms.

The man who once bellowed his opposition to US involvement in Syria sounded transformed as he announced his decision to launch air strikes on the Syrian air base that the Pentagon says was used by the Syrian regime to carry out a chemical weapons attack in the rebel-held Idlib region of the country.

“I call on all civilized nations to join us in seeking to end the slaughter and bloodshed in Syria,” Trump said, concluding with, “As long as America stands for justice, then peace and harmony will prevail.”

A day earlier at a White House press conference where he took up the chemical attack, Trump said, “I now have responsibility” for Syria.

It was the kind of discourse the world is accustomed to hearing from postwar American presidents – although less so from Barack Obama. Indeed, most Western leaders were quick to offer staunch support for Trump’s airstrikes – and, by extension, his donning of America’s mantle of responsibility.

For many world leaders, America’s leadership is indispensable, if not always appreciated – thus the alarm that echoed globally when an isolationist candidate won the White House.

“America is the pillar of the global international order, and that is not a pillar the world can easily do without at a moment of unprecedented challenges,” says Milliband.

Milliband has been critical of the signs from Trump of a turning away from the world. This week he took to Twitter, for example, to note that the president’s proposed cuts in foreign assistance are incompatible with his post-airstrikes call to the world to join the US in addressing Syria’s humanitarian tragedy.

But he says the criticisms of aspects of how America has carried out its global role do not mean the world is ready to carry on without it.

Protecting US interests

What Trump is learning, Georgetown’s Dr. Lieber says, is that while the worldview he espoused in the campaign would be welcomed by some and viewed with dismay by others, it would in either case undermine the US interests Trump wanted to focus on first.

“This is not the post-cold war world where US leadership was unopposed, we have rising powers like China and Russia and Iran that have very different ideas of how the world should be,” Lieber says. “If the US pulls back, it disheartens our allies and emboldens our adversaries.”

Lieber says Trump’s nascent embrace of the world’s need for American leadership is reflective of a “struggle” in the White House between what he sees as the ascendant internationalists on the president’s foreign–policy team and the fading “nationalists.”

Indeed, Steve Bannon, the president’s chief strategist and the architect of Trump’s America-First worldview, reportedly is on the outs at the White House – pulled from the National Security Council’s team of permanent members and losing battles right and left on Trump’s foreign-policy direction.

At the same time, Lieber says a half-dozen “adults” with more traditional views of the exercise of US power – including Defense Secretary James Mattis and national security adviser H. R. McMaster – are expanding their influence with the president.

And as that influence grows, the America-First impulses seem to have ebbed – with more focus on international engagement.

A need for world leadership

From his seat at the helm of an international humanitarian organization, Milliband says he sees unprecedented crises – more refugees than at any time since World War II, extended conflicts sending millions of displaced people into Europe – that demand attention from the world power with the strongest hand in building the international order.

“We are in a situation where there is not just room for leadership but a real need for it,” he says, “and much of the world look to America for that.”

In his statement given after the Syria airstrikes, Trump cited the regional destabilization resulting from Syria’s war and the wave of refugees it has sent into Western Europe as challenges to US national interest that could not be left unattended.

Trump’s shift away from the isolationist lure and his turn to a more traditional exercise of American leadership won’t be applauded by all, including those who see mostly war and human misery in the wake of US interventionism.

And from the opposite perspective, Lieber says that “although robust involvement and leadership by the US cannot be a sufficient condition for security and world order, the evidence suggests it is a necessary one.”

That’s the perspective he believes the would-be bull-in-a-china-shop president is starting to grasp.

“The early signs are that Trump is understanding, if in a rather tumultuous manner,” he says, “that the kind of world we want to see can’t happen with an American retreat.”