If the new US administration sought to make it clear to Europeans that the transatlantic friendship is over, they could not have chosen a better way. Combined with a long list of demands delivered by the new US secretary of defence Pete Hegseth during his first visit to NATO headquarters in Brussels this February, Europeans realised that the US under Trump does not have Europe's best interests at heart.

However, likely without realising it, the US actually presented a perfect formula for real European strategic autonomy. Hegseth's main demands included Europe taking full responsibility for the continent's security with no or minimal US contributions, investing in its capabilities accordingly, and building up an efficient defence industrial base. Europeans duly noted the US demands. And since then, Europe has been working extra hours to meet these targets.

Time is relative, and in terms of almost any European coordination effort – especially if new regulation is involved – six months is but a blink of an eye. And yet the sense of urgency, induced by the worst European nightmare, US abandonment, has triggered a series of previously unthinkable leaps forward.

The placating strategy adopted by European leaders to deal with Trump has obscured just how much Europe has done in a short time. Already in March, the European Commission presented the Readiness 2030 White Paper for European Defence, including the ReArm Europe initiative with an ambition to unlock €800 billion for defence investment. Ramping up support for Ukraine has been front and centre in the EU's new initiatives.

According to the Kiel Institute for the World Economy, which tracks Ukraine aid, Europe had filled the gap of missing US aid by April this year. The EU opened the new €150 billion SAFE (Security Action for Europe) financial instrument for member states in late May, with 18 countries applying for defence-related loans from the instrument by the first deadline in July. And the EU is working on EDIP (the European Defence Industry Programme) that is meant to bring short-term programmes into a coherent framework.

Beyond EU initiatives, wider Europe has not been sitting on its hands either. The UK has played a central role in supporting Ukraine and is now back among the big European countries – not only in the old Western European E3 format with France and Germany, but also in the Weimar+ format, a diplomatic framework that includes Poland and a varying cast of others. Most importantly, this summer has seen a Franco-British rapprochement of previously unthinkable extent.

France and the UK have been leading the coalition of the willing, which was set up in response to Trump's efforts to push Ukraine into a ceasefire deal with Russia in early spring. The coalition has coordinated support for Ukraine and prepared military plans in case Trump succeeds in brokering a ceasefire, but the US refuses to take responsibility for its outcome. So far, the plans have remained untested.

The coalition has several advantages over NATO and the EU: Ukraine is already included, unlike in NATO, where its membership remains blocked. Hungary, which routinely stalls EU aid to Ukraine, never joined the coalition. The US has not been part of it either, apart from attending a meeting in July. A number of partners from the Indo-Pacific, such as Japan and Australia, are members of the coalition. US allies have thus established a forum without the US.

The coalition is expected to be institutionalised with a headquarters in Paris rotating to London after 12 months, in classic European style. It has convened regularly at the highest political (heads of state) and military (chiefs of defence) levels, and could evolve into a more permanent structure if needed.

Last but not least, France and the UK, Europe's only two nuclear powers, have agreed to begin coordinating their nuclear deterrents. A bilateral Nuclear Steering Group will cover all relevant areas, from policy to capabilities and operations.

This marks a historic shift for France, which has long rejected any such level of coordination with partners on its sovereign nuclear deterrent. France is, for example, the only NATO member that does not participate in the alliance's Nuclear Planning Group, a body where member states consult on nuclear policy.

So far, so good. Europe's main goal with Trump has been to buy time: a sudden and dramatic US withdrawal from NATO and Europe would open a dangerous window of vulnerability and possibly give Vladimir Putin bad ideas. In the six months since Vance's speech, Europe has used that time wisely.

But the downside of the strategy has been how it looks: repeatedly bending to ”daddy” Trump (if only rhetorically) makes Europe look weaker than it really is. The moment when Europe must find the courage to take a firmer stance, regardless of how ”special” its ties with the US may be, is getting closer with each of Trump's provocations.

While Europe continues to export fossil fuel infrastructure, subsidise polluters, and resist calls for loss and damage payments, the UN's highest court's decision has made it clear: inaction is illegal.

With that, Europe's colonial past comes into play. Some overseas territories of European countries, like those of France, the Netherlands and the UK, now face existential threats from rising seas and intensifying storms. With the legal groundwork laid, they may soon ask Europe for reparations.

The ICJ's ruling is a quiet legal revolution in international climate law. It makes clear that states are not free to act, or fail to act, without consequence.

According to the ruling, countries have binding legal obligations to cut their greenhouse gas emissions, protect human rights from climate-related harm, and align their national policies with science-based targets. Failure to meet these obligations can constitute an ”internationally wrongful act”, exposing governments to legal claims for restitution, compensation, or even cessation orders – legal demands to stop activities that cause further harm.

”This is a concern of planetary proportions that imperils all forms of life”, said ICJ president Judge Yuji Iwasawa.

The ICJ's advisory opinion doesn't create new treaties, but it interprets existing international law, including environmental principles, human rights law, and the Paris Agreement. The ruling is already being cited in courtrooms and is expected to shape future court decisions, reinforcing its authority far beyond The Hague.

And for those on the front lines of the climate crisis, like low-lying island nations, drought-stricken communities, and climate-displaced populations, the ruling offers something long denied: a path to justice.

The EU and its member states are among the world's top historic emitters – on average, Europeans emit nearly 70% more greenhouse gases per person than the world average. Since the Industrial Revolution, European countries have burned fossil fuels at an extraordinary scale, accounting for 22% of cumulative global emissions.

At the same time, many of the countries now suffering the worst climate impacts – Tuvalu, Vanuatu, Guyana, Mozambique – are former European colonies. And some territories still governed by European states, like French Polynesia or the Caribbean Netherlands, are among the most climate-vulnerable places on Earth. They have contributed little to the problem but are being hit hardest by rising seas, stronger storms, and food insecurity.

Europe's climate policies often promote lofty goals and moral leadership. But while it pledges action, it continues to export fossil fuel infrastructure, subsidise polluters, and stall efforts to deliver funding for climate-related ”loss and damage”. That contrast between words and action has long sparked criticism. Now, it opens the EU up to legal risk.

”Those who did the least to fuel this crisis deserve protection, reparations, and a future”, said Vishal Prasad of Pacific Islands Students Fighting Climate Change, one of the groups behind the push for the ICJ ruling.

Europe's reluctance to pay for past and present environmental harm will be, beyond hypocritical, legally indefensible.

Dr. Margaretha Wewerinke-Singh, an international sustainability law scholar, said the ICJ opinion strengthens the case for what she describes as legal decolonisation: ”It opens the door to claims – especially from vulnerable states and overseas territories – by confirming that countries can be held responsible for climate harm if they fail to meet their obligations”, she said to The European Correspondent. Legal success will still depend on proving a clear link between harm and state action, ”but that's increasingly possible. It's a major step toward accountability”.

What the Court delivered is, in effect, a recognition that climate justice cannot be separated from historical injustice. States that built their wealth on extractive economies and industrialisation – much of it driven by colonial expansion – must now reckon with their ongoing legal obligations to those they once ruled.

Even before the ICJ's landmark opinion, some European overseas territories were already challenging their parent states in court over climate inaction. In January 2024, Greenpeace Netherlands and residents of the Dutch-Caribbean island of Bonaire sued the Dutch government for failing to protect the island from climate impacts, with the case allowed to proceed by a Dutch court in September 2024. Similarly, in June this year, French NGOs challenged France's National Adaptation Plan for not adequately addressing vulnerabilities in overseas territories.

Overseas territories still under the authority of European states could, in theory, also bring claims against their parent states for failing to protect them from climate harm. While these cases would raise complex questions of standing and self-determination, the principle has now been legally articulated: even within hierarchical or postcolonial relationships, climate negligence is actionable.

The consequences of the ICJ opinion aren't limited to international lawsuits. Within Europe, the ruling could also undermine EU legislation that falls short of climate obligations, including the bloc's own flagship climate framework, the European Green Deal.

Under EU law, member states are required to reduce emissions by at least 55% by 2030 and reach net zero by 2050. But the ICJ's opinion raises the bar further, making clear that climate plans must represent the ”highest possible ambition” and align with the 1.5°C limit. Failing to do so could violate both political commitments and international legal obligations.

That puts growing pressure on the EU's current efforts to weaken or delay green legislation, particularly through the so-called Omnibus I package, which seeks to roll back parts of the Green Deal, including nature restoration and air pollution limits. Legal analysts warn that any drop in ambition could now face challenges in court and might even be ruled illegal.

”Every new law or climate plan will be measured against the 1.5°C limit”, said) David Frydlinger, partner at Cirio law firm. ”Unless EU policymakers bring strong proof that these plans are not weakening the EU's climate ambitions, they're likely to be struck down if challenged in court”.

The concern is echoed by climate finance expert Tsvetelina Kuzmanova of the University of Cambridge Institute for Sustainability Leadership: ”The current political trajectory in Brussels risks taking us at least a decade backwards”, she said, arguing the changes lag behind standards already set by leading companies.

In short, the ICJ has added legal teeth to what up until now were just moral arguments. Europe's climate policies will no longer be judged solely by Brussels – they're now being measured by international law.