Article 5 and Its Complexities

Article 5 serves as the cornerstone of mutual protection, stating that “an armed attack against one or more” in Europe or North America is to be regarded as “an attack against them all.” This clause is straightforward when faced with external threats, such as those posed by Russia, but it becomes complicated when the aggressor is NATO’s most powerful member—the United States.

Denmark’s Prime Minister Mette Fredriksen articulated the gravity of the situation, stating, “If the U.S. chooses to attack another NATO country, everything will stop.” Such an action would cast doubt on the alliance’s durability and effectiveness, potentially fortifying an already aggressive Moscow.

Impact on U.S. Foreign Policy and European Alliances

During the 2024 election campaign, former President Donald Trump indicated that he would not defend “delinquent” NATO members—those nations failing to meet the 2% GDP defense spending target. His then-Defense Secretary, Pete Hegseth, further emphasized in February that the U.S. was “no longer primarily focused” on protecting Europe. This rhetoric alarmed European allies but the ensuing diplomatic engagements leading to NATO’s June summit appeared to address some concerns.

Despite some positive interactions, including flattering remarks directed at Trump by NATO Secretary General Mark Rutte, there remain unresolved rifts among member nations. Marion Messmer of the Chatham House think tank noted that while the summit may have initially calmed tensions, its long-term effectiveness is questionable.

The uncertainty surrounding U.S. foreign policy—particularly in relation to Ukraine—has exacerbated tensions, as two failed American attempts to negotiate a cession of Ukrainian territory have led to significant unease among European partners.

The Territorial Aspirations for Greenland

The recent resurgence of U.S. interest in Greenland, particularly following the capture of Venezuela’s Nicolás Maduro, has reignited discussions about historical sovereignty. As tensions rise, some analysts assert it would be unrealistic to expect any of NATO’s 31 other members to intervene militarily if the U.S. attempted to seize Greenland.

Trump’s adviser Stephen Miller articulated this mindset, asserting that international relations are governed by power rather than treaties. The stark military disparity underscores this point: the U.S. maintains 1.3 million active military personnel compared to Denmark’s 13,100.

Financial projections from NATO indicate the U.S. is expected to spend $845 billion on defense in 2025, whereas the combined defense expenditures of the other member nations total $559 billion. This disparity illustrates the extent of U.S. military dominance.

NATO’s Credibility on the Line

Even if the U.S. were to claim Greenland, the NATO treaty lacks clear provisions for expelling a member state. However, NATO’s preamble commits allies to “live in peace with all peoples and all governments,” which historically has been invoked against communist nations during the Cold War.

A conflict among NATO members, even over a territory with a small population like Greenland, would severely undermine the alliance’s credibility, which has been built on mutual defense and peacekeeping for over 76 years. The recent climate of threats and instability raises concerns, particularly in light of the current Russian aggression in Ukraine.

As Messmer warns, the time for European states to rely solely on U.S. security guarantees is over; this period of transatlantic unity may be fundamentally altered, highlighting the need for increased civic engagement and a re-evaluation of government policy regarding regional security.