The possibility of a US kill switch that could shut down Europe’s internet may seem far-fetched, but it has become a real concern in European policy and technology circles. At the heart of the issue is Europe’s heavy dependence on three American giants—Google, Microsoft, and Amazon—which together provide about 70% of the continent’s cloud-computing infrastructure. This dominance has raised fears that a political crisis, or an order from an unpredictable US president, could weaponize cloud services and plunge Europe into digital chaos. Analysts warn that critical data could vanish, websites could go offline, and essential services like hospitals could be disrupted.
These anxieties were heightened by a recent episode in which Karim Khan, the top prosecutor at the International Criminal Court (ICC), temporarily lost access to his Microsoft Outlook account after the US imposed sanctions. Though Microsoft insists it never suspended services, the incident illustrated Europe’s vulnerability to outside interference. Robin Berjon, a digital governance expert, argues that Europe must take the risk of a US kill switch seriously, no matter how remote it may seem.
The discussion connects directly to Europe’s long-standing struggles with “digital sovereignty”—the ability to control its own technology and data systems. American firms dominate not just cloud services, but also operating systems, payment networks, and artificial intelligence. Even mobile platforms like Apple’s iOS and Google’s Android, as well as payment providers like Visa and Mastercard, remain firmly American. While European cloud providers such as OVHCloud, T-Systems, and Delos exist, their share of the market is limited, and they lack the global scale of their US rivals.
Some European governments are exploring alternatives. Germany’s Schleswig-Holstein is moving away from Microsoft products in favor of open-source options like LibreOffice and Linux. Denmark is piloting similar initiatives. Advocates argue that open-source software can meet most needs for email, word processing, and other functions, and that resistance to adoption is largely due to lack of awareness and misplaced cybersecurity concerns. Analysts predict a growing shift toward open-source and sovereign solutions within the next decade.
US companies, however, insist they already address sovereignty concerns. Google partners with European firms like T-Systems to grant local control over data encryption, while Microsoft promises legal action if ever forced by Washington to cut off European customers. Still, skepticism remains over whether such assurances would hold under political pressure.
Some experts, like Zach Meyers of the Centre on Regulation in Europe, suggest that a fully independent European cloud is unrealistic. Instead, he argues Europe should focus on areas where it could lead, such as industrial applications of AI or advanced chipmaking equipment, where Europe’s photolithography expertise gives it a foothold.
Meanwhile, former ECB president Mario Draghi has warned that Europe is lagging far behind the US and China in tech competitiveness. Only four of the world’s top 50 tech companies are European, hampered by fragmented regulations and markets across the EU. Without stronger policies and incentives, Europe risks remaining dependent.
Ultimately, while many believe an actual US kill switch is unlikely outside of extreme geopolitical conflict, the debate has forced Europe to confront its digital dependence. Policymakers now face a choice: either accelerate efforts to build technological independence, or remain exposed to the risks of reliance on US-controlled infrastructure. What once seemed a distant possibility has become a pressing issue, reminding Europe that even improbable threats must be taken seriously in an era of geopolitical uncertainty.