The United States has suspended its participation in the Permanent Joint Board on Defence (PJBD), the senior advisory body on North American continental defence that has operated continuously since 1940, accusing Canada of failing to make credible progress on its defence commitments. Deputy Defence Secretary Elbridge Colby announced the pause on social media, stating that Washington “can no longer avoid the gaps between rhetoric and reality” and linking the decision directly to Prime Minister Mark Carney’s critical remarks about US hegemony at the World Economic Forum in Davos in January. The move is the first suspension of the PJBD since its creation under the Ogdensburg Agreement, signed by President Franklin D. Roosevelt and Prime Minister William Lyon Mackenzie King, and marks a dramatic escalation in the fraying of the bilateral security relationship.

Viewed from Washington, the decision reflects President Donald Trump’s long-standing insistence that Canada and other NATO allies must increase defence spending to ease the US burden. The Pentagon has framed the pause as a reassessment of how the forum benefits shared North American defence, but analysts note the timing coincides with a broader deterioration in ties over tariffs, trade, and personal animosity between Trump and Carney. In Ottawa, the prime minister sought to downplay the significance of the board’s suspension, pointing to his government’s record of doubling defence spending and diversifying procurement towards Europe. However, Canadian commentators have warned against dismissing the move, arguing that Canada’s geography means its security is inextricably linked to that of the United States and that the suspension is a politically motivated tactic to undermine Canadian sovereignty.

From a historical perspective, the PJBD was established in a moment of shared existential threat during the Second World War, when Roosevelt pledged to defend Canada and Mackenzie King promised to prevent any enemy from using Canadian territory to attack the US. The board’s suspension, even if temporary, breaks a 85-year tradition of bilateral defence collaboration and introduces an unprecedented politicisation of what was once considered an apolitical mechanism for coordination. European and Asian observers are watching closely, as the move reinforces perceptions that the Trump administration is willing to weaponise long-standing alliances to extract concessions.

Looking ahead, the suspension is likely to compound the isolation that Canada already feels in its defence relationship with the US. While Carney has promised to “continue as we have begun” with his procurement diversification strategy, the decision creates immediate uncertainty for joint planning on NORAD modernisation and Arctic security. The ball is now in Ottawa’s court to demonstrate credible defence spending increases and to repair a relationship that, for the first time in generations, no longer operates on automatic pilot. The risk is that without a reset, the bilateral defence architecture that has underpinned North American security for decades could become another casualty of the transactional approach to foreign policy that currently dominates in Washington.