Vladimir Putin is shaping Europe from its fringes, one act of aggression at a time. Nearly four years into his full-scale assault on Ukraine, the 73-year-old Russian president has widened the battlefield — testing NATO’s defenses with hybrid assaults, drone incursions and old-fashioned fighter jets. 

With U.S. President Donald Trump eager to wash his hands of the conflict, Putin has pushed deep into Western Europe, testing the nerves of governments and voters unaccustomed to military threats. Drones, suspected to be of Russian origin, have shut down airports in Copenhagen and Oslo and buzzed over military facilities in Germany. France has accused Moscow of orchestrating political destabilization campaigns inside its borders. 

Putin has been Europe’s chief disruptor for more than a decade. A former KGB officer who rose to power amid the chaos of post-Soviet Russia, he has defined his rule through confrontation with the West — from the invasion of parts of Georgia in 2008 and the annexation of Crimea in 2014 to his full-scale assault on Ukraine in 2022. Each step has pushed Europe to rethink its security, economy and political unity, and each crisis has left Putin more deeply entrenched in power at home. 

Today, Putin is under unaccustomed pressure. Sanctions and the cost of war are weighing on the country’s finances and Ukraine has proved itself capable of striking deep into Russian territory. But his incursions have nonetheless sent shivers down the spines of European leaders, who are scrambling to find their way in a world in which they may no longer be able to count on Washington to come to their defense. 

Concerns about Russian aggression have driven Europe to rearm, with German Chancellor Friedrich Merz breaking decades-old taboos about military spending. Even the continent’s military powerhouses, like France and the United Kingdom, are scrambling to rethink billions of euros in industrial and military investment as they realize that fighter jets and nuclear arsenals are ill-suited for countering Moscow’s low-grade asymmetric attacks and acts of hybrid warfare.  

The question for NATO and the European Union is: Will Putin’s pressure ultimately make these alliances stronger? Or will the Russian president succeed in shattering the foundations on which they were built? Either way, Putin has already achieved part of his aim: throwing Europe off balance and making it clear he’s the one person nobody on the continent can ignore. 

Check out the full POLITICO 28: Class of 2026, and read the Letter from the Editors for an explanation of the thinking behind the ranking.