In spring 2025, the United States under President Donald Trump imposed massive punitive tariffs almost worldwide. Within days, not only the European export economy began to falter, old trade models lost their validity - and the transatlantic relationship lost its self-evidence. This book provides a comprehensive analysis of this caesura. Originally conceived as a fundamental work on the development and impact of US tariff policy on Europe, it became an acute crisis document due to the dramatic escalation of the second Trump administration. It combines economic analysis, legal classification and geopolitical interpretation to create an overall picture that shows: tariffs are no longer mere instruments of market regulation - they are levers of power politics, symbols of strategic dominance and an expression of a new, fragmented world economic system. Updated to include the so-called 'Liberation Day', the birthday of the tariff crisis, this work not only analyses the causes and consequences of the American measures, but also discusses the European Union's options for action: from counter-tariffs and WTO proceedings, to investment protection instruments and industrial policy, to new coalitions in the Global South. A highly topical, well-founded and argumentative book about economic dependency, political unpredictability and the beginning of a new world order, in which Europe's economic future is both on trial and on the starting block. It makes it clear: the next few years will be anything but boring.