If the only thing stopping him is his own mind, just how far will Donald Trump go?

If events of the past week have taught the world anything, it is that Donald Trump’s declarations must always be taken at face value. We also now know that, to his mind at least, there are few guardrails that can prevent him from simply doing whatever he likes.

Now, in an extensive interview with the New York Times, the US president has admitted as much. He said the only constraint to his powers is “my own morality, my own mind… it’s the only thing that can stop me”.

Asked whether his administration felt constrained by international law, he said: “It depends on what your definition of international law is”, adding: “I don’t need international law.”

Which is chilling enough – if it wasn’t also for the real-life consequences of this approach, which Europe witnessed this week.

Its leaders rightly rallied behind Denmark when the Trump administration made another grab for Greenland. In hindsight, they should have seen it coming. Shortly after he returned to the White House, Trump made no secret that he was keen to buy the semi-autonomous territory – which at the time was met with a gentle “no, but thanks for the offer” and some nervous laughter among Nato allies.

Now, Trump is “very serious” about taking Greenland, even though it belongs to a fellow Nato member, or to invade or annex it. But the US is unlikely to need to march in, because it does not need to. Under a post-war defence agreement, US troops are already stationed on the island. The Danish government has confirmed that its forces would shoot back if attacked.

If that’s what Trump’s new world order looks like, what else might be in store?

A potentially even greater risk is how, in a looming Russian crisis, Trump could leverage Nato itself. Rather than coming to an ally’s aid, as is set out under Article 5 – the cornerstone of the Alliance which holds that an attack on one is an attack on all – might the US offer protection only if the member state agrees to some kind of payment, perhaps land?

Protection would come at a price, perhaps with Greenland demanded in exchange. It would perfectly match Trump’s transactional view of alliances and his self-image as a dealmaker.

An escalation beyond Ukraine is no longer a distant nightmare; it is a plausible next step – one the UK, Germany and France are preparing for. Russia already probes European airspace, including near Denmark itself, through regular aircraft and drone incursions. Russian military exercises routinely simulate land incursions into Nato territory.

Now, Moscow does not need to defeat Nato outright to weaken it. It could test its cohesion and resolve via America’s willingness or otherwise to fight. Russia’s strategy has long relied on exploiting fraying political trust and social cohesion, because once guarantees look conditional, uncertainty spreads faster than tanks or treaties.

During his first term, Trump repeatedly spoke of alliances in terms of payments, demanding Nato allies pay for US defence. Just this week, he openly questioned whether Nato would be “there for [America] if we really needed them”.

Yet that claim ignores a central fact: Article 5 has been invoked only once – by the US after 9/11 – and it was met with overwhelming support from Nato members. Trump’s indifference to that history tells us everything about how he views the alliance.

This is precisely the outcome Russia has waited for. A single crisis in which protection is delayed or negotiated would confirm the Kremlin’s long-held belief that the alliance can be fractured from within.

Trump’s fixation on Greenland is being sold as a matter of national security, but it is really about leverage, dominance and short-term political gain. Trump is demanding and normalising an American security guarantee that can be renegotiated in a crisis.

For Europe, the real danger is not simply a shortfall in firepower, but fragmentation: frontline states scrambling for reassurance, others hesitating to pay the price, and all quietly calculating how exposed they truly are. The aftershocks of such a rupture – political fragmentation, social polarisation, and rising vulnerability to external interference – would ultimately prove more destabilising than any single territorial dispute, including Greenland itself.

As Trump openly questions the relevance of international law, the burden of upholding it shifts. Bodies such as the Atlantic Treaty Association work to sustain political cohesion around Nato’s founding principles. In parallel, Dr Mohammad Al-Issa, secretary general of the Muslim World League (MWL), introduced the Makkah Charter, endorsed by more than 1,200 Islamic scholars, explicitly rejecting political violence and extremism in adherence to international law. This is the sign that non-state and transnational actors will increasingly serve as a civil backstop against coercion.

Because that vacuum, where trust between states collapses faster than societies can adapt, is precisely what Russia seeks to exploit – and what Trump appears willing to create.

Emir Gürbüz is the managing partner at the Legart Law and Consultancy firm in Istanbul and a board member of the Atlantic Treaty Association