Trump wants to ‘test’ NATO’s Article 5 by sending allies to the US southern border

US President suggests testing NATO’s collective defence clause to protect the southern border, intensifying debate over alliance obligations.

• Trump suggests invoking NATO Article 5 to address US border security concerns
• Proposal would expand NATO's defense clause to cover illegal immigration issues
• Experts doubt allies will back treating migration as an armed attack.

Did our AI summary help?

US President Donald Trump on Friday suggested invoking Article 5 of the North Atlantic Treaty to protect America’s southern border from illegal immigration, a proposal that would stretch NATO’s collective defence clause far beyond its traditional military scope.

In a post on his Truth Social platform, Trump said calling on NATO allies to secure the border could “free up” large numbers of US Border Patrol agents for other duties, framing migration as a threat warranting alliance-level response.

The remarks come days after Trump questioned NATO’s reliability during his address at the World Economic Forum in Davos, where he asked whether the alliance would defend the United States if required. “The problem with NATO is that we’ll be there for them 100%, but I’m not sure that they’ll be there for us,” he said.

What Article 5 does, and doesn’t do

The North Atlantic Treaty Organization has 32 member states. Article 5 commits all allies to assist a member that comes under armed attack. The clause has been invoked only once, by the United States after the September 11, 2001 terror attacks.

Trump’s suggestion marks a sharp departure from precedent, as Article 5 has never been applied to domestic law enforcement or migration control. Legal experts note that treating illegal immigration as an “armed attack” would face immediate resistance from allies and raise questions about the scope of NATO’s mandate.

Alliance pressure returns

Trump reiterated his scepticism about allied support, saying he was unsure whether NATO members would come to America’s aid despite US military spending and deployments overseas. The comments revive long-standing tensions between Trump and European allies over burden-sharing and alliance commitments.

The renewed NATO criticism coincides with Trump’s focus on Greenland, where he has pressed for greater US control while saying he would not use force to acquire the Danish territory. European allies have objected to the idea, further straining transatlantic ties.

Border security push at home

The comments also underline the administration’s hard line on immigration in Trump’s second term. Border security has been prioritised through tougher enforcement measures, with Immigration and Customs Enforcement expanding staffing from about 10,000 officers to roughly 22,000, according to administration statements.