The Munich Security Conference begins this week amid tense US-Europe relations. A year ago, US Vice-President JD Vance stunned Europe by criticising its migration and free speech policies. Since then, the Trump White House has shaken the global order with tariffs, a Venezuela raid, and demands like making Canada the US’s “51st state.” US Secretary of State Marco Rubio leads the US delegation as more than 50 world leaders gather. Europe's security looks fragile. The US National Security Strategy from last year urges Europe to “stand on its own feet” for defense. This worries many who fear the US may reduce its role in European defense. The Greenland crisis deepened doubts. Trump has repeatedly said he “needs to own” Greenland, a Danish territory, citing US and global security. Denmark’s Prime Minister warned a hostile US takeover would end the NATO alliance that secured Europe for 77 years. The crisis is on pause but has shaken trust. Sir Alex Younger, former UK MI6 chief, says the alliance isn’t broken but changed. He supports Trump’s call for Europe to handle more of its own defense, noting the US (300m people) shouldn’t defend the larger European population (500m) against Russia (140m) alone. Beyond defense, the Trump administration and Europe split on trade, migration, and free speech. European leaders worry about Trump’s closeness to Putin and blaming Ukraine for Russia’s invasion. The Munich Conference report warns Trump weakened foundations built since World War II: multilateralism, economic integration, and democracy. The US National Security Strategy calls Europe a “shocking wake-up call” and suggests supporting groups that resist current European governments. It claims Europe’s migration policies threaten “civilizational erasure.” A key question is whether NATO’s Article 5 — the pledge that an attack on one member is an attack on all — still holds firm. The “Narva Test,” named after a Russian-speaking town in Estonia on the Russian border, asks: Would the US defend a NATO ally there or elsewhere like the Suwalki Gap or Svalbard? Trump’s unpredictability makes answers unclear and risks miscalculations amid Russia’s war in Ukraine. This Munich Security Conference may reveal how US-Europe security ties will evolve, though Europe might not like all the answers.