‘Home alone’: How Trump is changing security in Europe

It was dubbed the Winter War for good reason. In November 1939, months into World War II and almost completely overshadowed by events elsewhere in Europe, the Soviet Union invaded its neighbour Finland. Like Russia’s recent incursion into Ukraine, it didn’t go quite to plan.

Soviet forces greatly outnumbered the Finns but were not prepared for the harsh conditions: snow, ice and minus-45-degree temperatures. Many Soviet troops suffered from frostbite (as would the Nazis in Stalingrad in 1942). The Finns, meanwhile, put up a stubborn resistance. They camouflaged themselves in white, skied about, dragged supplies on sleds pulled by reindeer, dug foxholes in snowdrifts and fought with whatever came to hand, including an improvised grenade they named after Soviet minister Vyacheslav Molotov – the petrol bomb known today as the Molotov cocktail. “They fought like white demons, to the last frayed nerve of resistance,” recalled a photographer for Life magazine in January 1940.

It was a brutal, bloody conflict. After just 105 days, the Finns had suffered 100,000 casualties, the Soviets close to 400,000. But Russian air support proved overwhelming as did waves of troops that Life called the “Red juggernaut”. Backs against the wall, the Finns were forced to sign a peace deal with Moscow and had to cede a tenth of the territory along their 1300-kilometre border.

And so the scene was set for Finland’s complex relationship with its belligerent neighbour. After WWII, when Europe’s biggest security pact, the North Atlantic Treaty Organisation, formed at the beginning of the Cold War, Finland stayed neutral, hoping to diplomatically negotiate its own path with the Soviet Union (now Russia) rather than hide beneath NATO’s skirt. “The Finns have tried to cultivate a relationship with Russia,” Professor Juhana Aunesluoma tells us from the University of Helsinki. “As long as you have dialogue, as long as you have meetings between the governments, the border authorities collaborate, everything works.”

That was until 2022, when it all got a bit too real with Russia’s full-scale invasion of another of its neighbours, Ukraine. In Finland, sentiment towards NATO flipped overnight. It became the newest member of the alliance, soon followed by Sweden.

Now, the script has flipped again. With the ascension of US President Donald Trump, Europe’s main strategic partnership seems increasingly less assured. NATO, under US leadership, has so far guaranteed defence for Europe. But, if you take Trump at face value, it might be in jeopardy. “How reliable the Americans are is now the talk of town,” says Aunesluoma. “People are discussing whether, in a conflict, would the Americans still be supplying rockets to the rocket launchers that we have here in Finland?”

How has Europe defended itself so far – and how will that change? What role has NATO played and can it continue? What’s the new “coalition of the willing”?

How has Europe defended itself so far?

The fiery Oval Office meeting is now infamous: Ukrainian president Volodymyr Zelensky trying to school Trump and Vice President J.D. Vance as the American leaders laid bare that they would not support Ukraine against Russia as enthusiastically as president Joe Biden had for almost three years. “The attitudes need to change,” Trump told the onlooking media. Days later, he reiterated the US might not play its historic role protecting European members of NATO unless they were prepared to pay more for their own defence.

Exactly what Trump was threatening was, typically, slightly opaque. Nevertheless, he prompted a panicky response in Europe, where NATO member states are now figuring out how to fund more of their own defence and even to take the lead to support peace in Ukraine. In the background of this shift in Europe’s security architecture sits NATO: the North Atlantic Treaty alliance, responsible for protecting most (but not all) European nations (plus the US and Canada) from hostile forces (for a long time, the Soviet Union).

The alliance was established after World War II when 12 founding parties signed the Washington Treaty in 1949 as a way to counter the Soviet Union’s expansion beyond Eastern Europe. As the Cold War escalated in the 1950s, more nations joined, especially those at risk of Soviet invasion or communist takeover, such as Greece and Turkey in 1952. West Germany’s entry in 1955 spurred the Soviets to bind satellite socialist states through the Warsaw Pact, joining Hungary, Czechoslovakia, Poland, Bulgaria, Romania, Albania and East Germany in a collective defence treaty.

Scares such as the Cuban missile crisis of 1962 put NATO forces on high alert: US president John F. Kennedy and Soviet leader Nikita Khrushchev faced off over Soviet nuclear missiles pointed at the US from communist Cuba, placed there after NATO installed its own missiles in member nation Turkey. (Khrushchev dismantled the Cuban sites after NATO secretly agreed to remove its weapons from Turkey.) Fast-forward and Soviet invasions of Czechoslovakia in 1968 and then Afghanistan in 1979 were seen by the West as evidence of continuing aggressive ambitions.

By the 1980s, the prospect of Soviet tanks roaring across Western Europe or even all-out nuclear war seemed frighteningly real. Lined up on the borders of East Germany, Poland, Czechoslovakia and the rest of the Iron Curtain nations were at least 4 million Warsaw Pact troops, supported by some 60,000 tanks and nearly 13,000 aircraft. Staring back across the barbed wire, NATO forces numbered nearly 2.6 million troops backed by some 2000 nuclear-ready planes and missiles: not enough to hold back the hordes but probably sufficient to delay them until reinforcements could arrive from the US … or the conflict escalated into Armageddon.

Popular culture reflected this anxiety: in 1984 alone, the BBC screened Threads, a shockingly realistic film depicting the aftermath of an atomic strike on a British city; Tom Clancy published The Hunt for Red October, a tale of a Russian nuclear submarine gone rogue (whose captain was later played in the film adaptation by Sean Connery); ABBA alumni Benny and Bjorn launched the chess-tournament musical Chess, an allegory for the Cold War; and the band Frankie Goes to Hollywood had a No.1 hit with Two Tribes, which opened, alarmingly, with the sound of the siren that would accompany an imminent nuclear attack.

By the end of the decade, though, fears of this existential threat had somewhat diminished. Under a critical arms treaty signed in 1987, the US and the USSR agreed to ban shorter-range missiles. The Berlin Wall came down in 1989, East and West Germany reunified in 1990, and in 1991, the Soviet Union collapsed. For NATO, having deterred warfare for all those years, this was equivalent to victory: job done. “When the Soviet Union collapsed in 1991, NATO lost its rational purpose as a deterrent to Moscow,” says Benjamin Abelow, author of How the West Brought War to Ukraine.

NATO did intervene in its first conflict in a non-NATO country from 1992, when it sent air support and then peacekeepers into the Bosnian conflict. And NATO troops went to Afghanistan in 2001 (more on which below). But much of the discussion about NATO’s role centred more on appropriate levels of funding than the need to stay battle-ready at all times.

In Europe, an alliance goal was building a community among nations, says Sten Rynning, a war professor at the University of Southern Denmark and author of NATO: From Cold War to Ukraine, A History of the World’s Most Powerful Alliance. “It moved outside of NATO into the European Community, now the European Union. Today, you have to understand that the European Union is a child of NATO.” (Most EU members are in NATO but not all: Cyprus, Ireland and Malta are not, nor is Austria, whose constitution prohibits it from joining any military alliance. Most NATO members are in the EU but some are not: apart from the US and Canada, there’s Albania, Iceland, Montenegro, North Macedonia, Norway and Turkey. Britain used to be in both but isn’t now, thanks to Brexit. Finally, not in either camp is perma-neutral Switzerland.)

Meanwhile, of course, Russia was licking its wounds, and under Vladimir Putin it was reviving its territorial ambitions. “Putin’s actions should be viewed in a historical context,” says Gorana Grgic, a senior lecturer in US politics and foreign policy at the University of Sydney. “The full-scale invasion of Ukraine is not an abrupt shift but rather the culmination of years of failed attempts to reassert Russian control over Ukraine and Russia’s near abroad.” And Russia’s so-called grey-zone activities, those below the threshold of outright military conflict, have been prolific for much of the past two decades, notes Grgic, including “assassination plots, sabotage, information operations and political interference”.

Says Abelow: “Many still view NATO through the prism of its early days, when it confronted a Soviet Union that proclaimed an expansionist Communist ideology. But to Russia, during the period after the end of the Cold War, things began to look very different. Keep in mind that NATO is the most powerful military alliance in the history of the world. Russia came to perceive it as a threat, especially when it carried out military exercises on or near Russia’s borders.”

NATO members are bound to mutual obligations detailed in 14 “articles”, of which Article 5 is the best known. Its simplest definition is that it considers a military attack on any individual member nation to be an attack on all. It is commonly misunderstood as requiring all of NATO to immediately go on a war footing if a single member is attacked. In fact, the obligation is a little looser, expecting each member to take “such action as it deems necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area”.

In practice, this means allies can provide any form of assistance they deem necessary to respond to a situation. (When the treaty was drafted in the 1940s, European countries wanted to guarantee that the US would automatically come to their assistance, the Nazis being a recent memory, while the US wanted the option to decide for itself how it might intervene.) NATO’s Supreme Headquarters Allied Powers Europe (SHAPE) is in Belgium while its air force HQ is in Germany, land forces in Turkey and maritime forces in Britain – yet these forces are not its own. Instead, it has the capacity to bring national forces under its command, equating to some 3.4 million troops across the alliance.

In more than 70 years, Article 5 has been invoked just once, when NATO sent troops to Afghanistan, triggered by al-Qaeda’s attack on the US on September 11, 2001. At one stage, there were more than 130,000 NATO troops on the ground. Curiously, it was not invoked when Argentina invaded the Falkland Islands in 1982, an attack on founding member Britain. This was because of the lesser-known Article 6, essentially a fine-print addendum to Article 5, which, among other conditions, limits NATO obligations to attacks that occur only above the Tropic of Cancer, thus excluding the Falklands.

Why isn’t Ukraine in NATO?

While members can invite into NATO any European state that is “in a position to further the principles of this Treaty and to contribute to the security of the North Atlantic area”, politics plays a role. Turkey and Hungary, for example, initially blocked Finland. “Eventually, probably because of pressure from the United States, they came on board,” says Christian Reus-Smit, a professor of international relations at the University of Melbourne. “But if the US isn’t going to be a party to it, it’s not going to happen.”

In the late 1990s, NATO began to promote an “open door policy” for new members after inviting in Poland, the Czech Republic and Hungary. In 2008, US president George W. Bush said he “strongly supported” Ukraine’s and former Soviet republic Georgia’s bids to join NATO but France and Germany resisted, saying the moves risked needlessly angering Russia. Four months later, Russian troops invaded Georgia. Ever since the ensuing conflict, which was over in days, the question of Georgia’s membership has been on hold. Meanwhile, support to join grew among Ukrainians. The US told Kyiv the pathway to membership would involve democratic, economic and military reforms. And then-NATO secretary-general Jaap de Hoop Scheffer said Ukraine could join eventually, without specifying a timeframe.

In 2010, Ukraine opted to pursue a non-alignment policy, choosing not to join any military alliances, but there was a groundswell for joining the European Union. In 2013, Ukraine’s pro-Russia president Viktor Yanukovich refused to sign an agreement with the EU, and civil unrest took hold in Kyiv, later known as the Maidan Revolution that, ultimately, led to Yanukovich’s overthrow in 2014. “NATO was never on the table at that point,” says Steven Horrell, a senior fellow at the Centre for European Policy Analysis in Washington DC.

After Russia (or its unbadged “little green men”) annexed Crimea, a peninsula in Ukraine on the Black Sea in 2014, Ukraine abandoned its non-alignment policy. Then, after the start of the all-out war in 2022, support for NATO membership rose to 80 per cent, according to the Kyiv Independent. In 2023, NATO jettisoned the need for Ukraine to follow a membership plan, ensuring it could join in the future in a one-step process. NATO’s website states: “Ukraine’s future is in NATO”.

Zelensky has gone so far as to say he would “trade” his leadership for NATO membership. Russia has consistently objected to Ukraine joining NATO. Currently, the UK, France, Italy, Poland and the Baltic states have supported it, while the US, Germany, Hungary and Slovakia have said they don’t yet. Says Horrell: “This is not just a political club, it’s a functional alliance designed to provide collective security. If it will ultimately be destabilising, or decrease security, then it’s not a good idea to let them in.”

The holding pattern that Ukraine has been in since 2008 hasn’t helped its situation, says Ann Dailey, a policy researcher at US think tank the RAND Corporation: “One could question the political wisdom of a NATO membership accession process that left nations like Ukraine in diplomatic limbo by declaring they would eventually be members without actively working toward that goal or seeking to deter aggression against them while they worked toward accession.” Other countries that have pursued joining the alliance include Georgia, and Bosnia and Herzegovina.

For now, NATO has made clear it supports Ukraine’s right to self-defence, and has overseen a Comprehensive Assistance Package, launched in 2016, which as of February had contributed $1.5 billion via allies and partners for medical and defence equipment, among other long-term investments. In February, NATO also announced the Joint Analysis Training and Education Centre with Ukraine in Bydgoszcz, Poland, which will use lessons from the conflict to inform defence planning.

How will Europe’s security change in coming years?

Days after Trump and Zelensky’s cringe-watch meeting, British Prime Minister Keir Starmer stood in the gilded interiors of Lancaster House, London’s forum for diplomacy (and the home of the government’s wine cellars), and announced that a “coalition of the willing” led by Britain and France would step in to play a defensive role under any peace deal between Ukraine and Russia.

Starmer described the prospective group – which could number about 20 European and Commonwealth countries – as “ready to support Ukraine with troops on the ground and planes in the air”. (Anthony Albanese has indicated Australia’s willingness to contribute to a peacekeeping force.) French President Emmanuel Macron later said any peacekeeping force “must be credible and conceived for a long-term commitment, must give unfailing support to the Ukrainian army and should not be disconnected from NATO and its ‘capacities’.” So, NATO … but not NATO.

The new US Defence Secretary, Pete Hegseth, meanwhile, has called on nations supporting Ukraine – a grouping of 57 countries in the Ukraine Defence Contract Group, which includes all NATO states – to “meet the moment”: “This means donating more ammunition and equipment, leveraging comparative advantages, expanding your defence industrial base,” he said in February, “and, importantly, levelling with your citizens about the threat facing Europe.” During talks in recent days, Ukraine has flagged it is open to a 30-day ceasefire proposed by the US. The Kremlin is reviewing the details.

Meanwhile, debates that go back to the ’50s over how much the US should pay for Europe’s defence continue. The US has always played an outsized role in NATO: it contributes the equal-biggest share of spending with Germany at almost 16 per cent (followed by the UK at 11 per cent and France at 10 per cent). Trump wants all NATO countries to up their contribution to 5 per cent of GDP; in 2014, they agreed to commit 2 per cent but NATO’s latest figures, estimates for 2024, showed eight countries wouldn’t meet the target.

“We are in an era of rearmament,” European Commission head Ursula von der Leyen said last week, unlocking $1.3 trillion in “special funds” for defence. The UK and France have flagged increases to their defence spending, and Germany’s likely next chancellor Friedrich Merz has said “the rule for our defence now has to be ‘whatever it takes’.”

Macron has also said he would open a “strategic debate” about using France’s nuclear weapons “to protect our allies on the European continent” – a statement that would have been inconceivable even six weeks ago, notes Sten Rynning, of the University of Southern Denmark. It quickly raised the ire of Putin, who said, “There are still people who want to return to the times of Napoleon, forgetting how it ended.” (Napoleon suffered humiliating defeat in his invasion of Russia in 1812.)

Observes David Swanson, co-author of the 2024 book NATO, What you need to know: "The possession, never mind the increasingly reckless proliferation, of nuclear weapons, given the great number of near misses already survived, is probably not survivable for very much longer.”

There’s a lot of emotion in this debate in Europe, notes Rynning: feelings of abandonment by the US, sympathy with Ukraine and the moral element of Europeans protecting their values. “The biggest change is that Europeans are now home alone. The parent has left the room. This is structural.” Yet Europeans can’t take over defensive leadership of their continent overnight. “You have to understand that NATO is built on a division of labour, and the US has the leading role in terms of the strategic labours. Call them intelligence, communication systems, command and control, airlift, air defence systems – all of that is very heavily dependent on the US.”

Historians and analysts see the interweaving of European nations with institutions such as NATO and the EU as key pillars to the success of the post-World War II “European Project”. “The idea was that by integrating these states and making them more and more interdependent with each other, there was less chance that they would come into conflict with each other,” says Christian Reus-Smit of the University of Melbourne. “That’s a really momentous achievement. But this project has really had a hard time in the past decade or 15 years. Brexit was, of course, the biggest casualty to it.” Britain left the EU, but not NATO.

As for any US exit, even if he wanted to, Donald Trump would find it tricky to leave. For a start, the National Defence Authorisation Act specifically prohibits the US president from unilaterally withdrawing from NATO without approval of a two-thirds Senate super-majority or an act of Congress. If somehow the US did abandon NATO, one scenario is its bureaucracy could survive but it “effectively ceases as an alliance”, says Rynning. “I’m not entirely that pessimistic. I think cool heads on both sides of the Atlantic will prevail. On the European side, they know we need time and we need to do this in partnership with the US. On the American side, I think cool heads know that at some point Trump’s America will be tested. Be that from Russia or China, Iran maybe, North Korea. And at that point they need allies and partners.”

Back in Finland, while NATO troops will soon be based in Lapland’s capital, Rovaniemi (more famous as the home of Santa Claus), and further north in Sodankyla, Trump’s second term has introduced an element of doubt for the likes of Juhana Aunesluoma from the University of Helsinki. “If there’s an incident somewhere,” he muses, “you know, if the Russians do something big or small, how would the American president react? We know NATO has procedures in place, but would the NATO commanders get the green light from Washington?”

Still, after decades outside NATO, the Finns have form in self-sufficiency, he tells us. “Finns are worried, really worried because we do face Russia, but Finns have a bit more confidence in their ability to handle all kinds of situations.”

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