Donald Trump is practically alone in mainstream American politics in his consistent praise of Vladimir Putin and insistence that the United States would benefit from warmer relations with Russia. But that inclination to view Putin more as ally than adversary places Trump squarely in line with the racially infused, conservative-populist movements gaining ground in both America and Europe.

And that means the intra-GOP friction over Russia between Trump and more traditional foreign-policy thinkers like Senators John McCain of Arizona and Lindsey Graham of South Carolina points toward a much larger debate over the priorities that should drive American foreign policy.

Across the political spectrum, mainstream foreign-policy thinkers in both the United States and Europe view Putin as a threat largely because he is pushing to expand Russian influence across eastern Europe and the Middle East in ways that could destabilize the U.S.-led system of alliances and global rules that has defined the international order since World War II. That concern has spiked amid a succession of provocative actions from Putin, ranging from his 2014 incursion into Ukraine and brutal military campaign against anti-government rebels in Syria, to the U.S. intelligence community’s conclusion that Russia hacked Democratic Party email accounts to influence the 2016 American presidential election. (Trump, due to receive an intelligence briefing about those conclusions on Friday, has steadfastly resisted and belittled that conclusion.)

But the conservative-populist nationalists in both the United States and Europe view Putin as a potential ally because they are focused on a sharply contrasting set of international priorities: resisting Islamic radicalization, unwinding global economic integration, and fighting the secularization of Western societies. Top Trump advisers like incoming White House chief strategist Stephen Bannon and National Security Adviser Michael Flynn have expressed strikingly similar views.

In that way, the clashing perspectives on Putin reflect not only differences on how to relate specifically to Russia, but on what goals should guide American foreign policy in the 21st century, and what allies are necessary to advance those aims. On both sides of the Atlantic, the push to reset with Putin reflects a desire to elevate a different set of foreign-policy concerns while downplaying, or even abandoning, the alliances that have bound European nations more tightly to each other, and to the United States, for decades.

One critical variable of the Trump presidency may be how far this radical shift in perspective advances in a Republican Party where most elected officials and foreign-policy analysts still believe global stability depends on an American-led network of rules and alliances, and still view Putin as an escalating threat to that order. Though the conservative-populist embrace of Putin common in Europe remains confined to the GOP’s margins, it appears to be establishing a beachhead under Trump, noted Richard Fontaine, president of the centrist Center for a New American Security, and the former top foreign-policy aide to McCain. “It’s already going further than I expected it to go,” Fontaine said in an interview. “The fact that dyed-in-the-wool Republicans are going out and suggesting we don’t know who hacked what [in the 2016 campaign] and the sanctions may be an overreaction is not a terribly encouraging sign.”

The major conservative nationalist and populist movements in Europe, including France’s National Front, Britain’s U.K. Independence Party, Germany’s Alternative for Germany, the Netherlands’s Party for Freedom, Austria’s Freedom Party, and Hungary’s Jobbik, don’t completely overlap in their views of Putin. Geert Wilders, the leader of the Party for Freedom, for instance, has been cooler toward Putin than the National Front’s Marine Le Pen, who borrowed from a Russian bank to help fund the party’s 2014 electoral campaign, or the Freedom Party, which recently signed a “cooperation agreement” with Putin’s United Russia party.

But the European populist parties share a common set of priorities focused on restricting immigration, unwinding global economic and political integration (by renouncing the European Union, and, for some of these parties, NATO as well), taking tougher steps to fight Islamic radicalism, and, in most cases, opposing cultural liberalism and secularization at home. On all those fronts, they view Putin not as a threat, but as an ally.

“It’s certainly not that they follow him the way Communist parties used to follow the Soviet Union. That’s a misrepresentation,” said Cas Mudde, a University of Georgia associate professor of international affairs who studies these movements. “But … they do like his strength, what they perceive as defense for strong traditional values, nationalism, and opposition to Islam.”

On each of those concerns, Putin has positioned himself as a bulwark of conservative values. First in Chechnya and more recently in Syria, he can claim to have taken the fight to Islamic extremists, perhaps more aggressively than any Western nation since America overthrew the Taliban in Afghanistan (of course, Russia’s Syria campaign has focused far less on combating the Islamic State than on obliterating opponents of President Bashar al-Assad’s regime). Conservative populists like Le Pen have hailed Putin’s hostility toward global institutions as a model for prioritizing nationalist independence over multilateral cooperation and integration. “The model that is defended by Vladimir Putin is radically different to that of Mr. Obama,” Le Pen told a British television interviewer last November. “As for me, the model that is defended by Vladimir Putin, which is one of reasoned protectionism, looking after the interests of his own country, defending his identity, is one that I like, as long as I can defend this model in my own country.”

Particularly since his return to the Russian presidency in 2012, Putin has portrayed himself as a defender of traditional social values, especially in opposition to gay rights, and as a religiously devout alternative to Western countries that he has said “are denying moral principles and all traditional identities: national, cultural, religious, and even sexual.” While the idea of Putin lecturing the world on “moral principles” grates on mainstream ears, that stance has also drawn praise, not only from conservative populists in Europe, but also like-minded American activists, like columnist Patrick J. Buchanan, whose 1996 bid for the GOP presidential nomination presaged many of Trump’s insular themes.

Against these shared priorities, the European populist parties almost universally downplay Putin’s destabilizing moves, including those in Ukraine and the annexation of Crimea, as, at most, a second-order concern. Nigel Farage, a founder of the U.K. Independence Party and the European populist leader personally closest to Trump, has said that while Putin’s incursion in Ukraine was not justified, it was an understandable response to Western overreach. “The Ukrainian crisis actually was sparked by the European Union saying they wanted to extend their borders to take in the Ukraine, which Putin took as being a direct threat,” Farage told Fox News last summer. “Now, my view on Putin and the Russians is, don’t poke the Russian bear with a stick. If you do, you’re bound to get a response.”

Farage’s take is common among Europe’s conservative populists. “They don’t think that Russia wants to reinstate a Soviet Union. They consider Russia pretty much defending itself against globalism, and they would like to have the EU or NATO out of central and eastern Europe,” Mudde said. “But they don’t assume that Russia then moves back in. Russia is of no concern to them. They don’t believe Russia has ambitions to threaten western Europe.”

To a striking extent, top Trump advisers Flynn and especially Bannon have expressed similar views in recent years. In an extensive 2014 speech at the Vatican unearthed by Buzzfeed, Bannon echoed common arguments from the European nationalist parties to explain why people he called “traditionalists” were drawn to Putin. Bannon portrayed Putin as championing both nationalism and conservative cultural values. “One of the reasons [Putin is attractive to ‘traditionalists’] is that they believe that at least Putin is standing up for traditional institutions, and he’s trying to do it in a form of nationalism—and I think that people, particularly in certain countries, want to see the sovereignty for their country, they want to see nationalism for their country,” Bannon said. “They don’t believe in this kind of pan-European Union or they don’t believe in the centralized government in the United States.” Later, Bannon added: “Putin’s been quite an interesting character. He’s also very, very, very intelligent. I can see this in the United States where he’s playing very strongly to social conservatives about his message about more traditional values.”

To a greater extent than the European populists, Bannon was careful to also criticize the Russian leader, saying “Putin and his cronies [are] a kleptocracy, that are really an imperialist power that want to expand.” But like Europe’s right-wing populists, Bannon immediately argued that the potential threat Putin posed ranked below more pressing concerns, like allying with the Russian leader against Islamic terrorism. “I really believe that in this current environment, where you’re facing a potential new caliphate that is very aggressive that is really a situation— I’m not saying we can put it on a back burner—but I think we have to deal with first things first.”

Flynn, former director of the Defense Intelligence Agency, similarly suggested sublimating American concerns about Russian behavior to the struggle against Islamic terror during his controversial visit to Moscow in December 2015. “I am speaking as [a] private citizen, but the U.S. can’t sit there and go: ‘Russia, you’re bad;’ Russia can’t sit there and be ‘U.S., you’re bad!’” Flynn said in an interview on RT, Russia’s state-owned English-language television network. “I think that we have to step back and we have to say: ‘Okay, what are the common interests, and what are the common goals that we want to achieve’—and … I believe, the number one goal is to eliminate this cancerous idea that exists inside the Islamic religion.”

Expanding the argument, Flynn suggested that the new threat of global terror required a fundamental shift in priorities that would position the United States and Russia less as competitors than as collaborators in a common fight. “[W]e have to begin to understand that this is not an East-West world, folks, [that it’s] actually more of a North-South world, and we have to decide—U.S., Europe, Russia and other, other countries, countries in South America, maybe, and even China and India, how do we want the world to be over the course of the next 10 years, 25 years, 50 years?” Flynn added. “[I] don’t believe for a second that we’re going to defeat the Islamic State in two years. This has been described as a 100-Year War.”

How many of these views Trump personally shares is unclear. He has said strikingly little about why he believes better relations with Putin would advantage the United States, other than to broadly suggest the two nations could work together more effectively against ISIS. Many analysts see Trump’s attraction to Putin as mostly a personal connection driven both by Trump’s admiration for his tough-guy style, and Putin’s careful flattery of the president-elect.

But Fontaine, the former McCain aide and CNAS president, said a tilt toward Putin would be compatible with two larger foreign-policy tendencies Trump has hinted at. One is an inclination to view “China as the bigger threat” to the United States both because of its aggressive posture in Asia and because it represents a much more formidable economic competitor than Russia.

Trump has said strikingly little about why he believes better relations with Putin would advantage the U.S.

Second, Fontaine noted, Trump at various points has suggested—particularly in his comments about Asia—that he is more comfortable trying to maintain global stability through regional “spheres of influence” led by locally dominant powers than through “one unified world order in which American power is the ultimate foundation.” Through that lens, Fontaine continued, Russia’s attempts to expand its reach in eastern Europe “may not be as concerning to you than if you are concerned that it is undermining the rules-based system of the world.”

So far, Fontaine said, this more benign assessment of Putin has very little support among elected officials in either party. “Almost everybody thinks if we can find some way to work with Russia on discrete issues, [then] sure [let’s pursue those opportunities],” he said. “But that there is no overarching deal, or friendly bond between the U.S. and this Russia that can be had either without compromising fundamental interests or principles, or seeing the agreement go up in smoke when Russia violates it.”

McCain offered the rallying cry for that competing view in his bristling opening statement at Thursday’s Senate Armed Services Committee hearing on Russian hacking and other cyber threats. “It should not surprise us that Vladimir Putin would think he could launch increasingly severe cyberattacks against our nation,” McCain insisted, “when he has paid little price for invading Ukraine, annexing Crimea, subverting democratic values and institutions across Europe, and of course, helping Bashar [al-]Assad slaughter civilians in Syria for more than a year with impunity.”

And yet both in America and in Europe, electoral momentum has been growing for the conservative-nationalist and populist movements arguing for a fundamental reassessment of global alliances that would include a reset of relations with Russia. The depth of Putin’s commitments to these movements is likely shallow: As Mudde noted, Russia has touted left-wing parties in Europe as well when that suits its interests. But Putin has also clearly demonstrated that he views the rise of conservative nationalism as an ally of convenience in a goal that suddenly seems more obtainable than at any time in decades: loosening the Western alliance from both its American and European moorings.

“I don’t think we should underestimate the degree to which the undermining of the fabric of Western society is a fundamental aim of what Putin is all about,” said Ivo Daalder, President Obama’s former permanent representative to NATO and now president of the Chicago Council on Global Affairs. “We are in a very different time period that has far more to do with the 1920s and 1930s than it does with 2010. We are at a tipping point where the success of these [populist] movements raises fundamental question about the [viability of the] international order we are living in.”

Atlantic assistant editor Leah Askarinam contributed.