The Issue Brief examines what the 2026 Greenland crisis reveals about evolving U.S. alliance expectations and highlights that the episode reflects a broader shift in how Washington manages its alliances.

The Greenland crisis was triggered in early 2026 with President Donald Trump’s renewed interest in acquiring Greenland, who framed the issue as vital to U.S. national security and Arctic strategy. While tensions de-escalated after Trump pledged not to use force to annex Greenland, it generated significant concern across Europe and raised questions about alliance cohesion within NATO.

The Issue Brief argues that the episode reflects growing U.S. frustration with allied burden-sharing and signals a shift toward more assertive forms of alliance management, including political pressure and the threat to use military force to elicit greater contributions from partners.

The Issue Brief further highlights how European allies responded with a calibrated approach, combining firm defense of sovereignty with efforts to avoid escalation. In this context, the Issue Brief identifies two key trends shaping U.S. alliances today: increasing expectations for allied contributions and a widening gap in perspectives between the United States and Europe regarding the future of the transatlantic relationship. These dynamics are not confined to Europe but are relevant across the broader U.S. alliance network. The Issue Brief concludes with two lessons South Korea should bear in mind as it navigates a more unpredictable alliance environment. 

The views expressed herein do not necessarily reflect the views of the Asan Institute for Policy Studies.