History does not repeat itself. But the structures that shape power can return in recognisable forms.On the Precipice examines how old patterns of domination, dependence and strategic vulnerability reappear under new political and institutional conditions.Beginning with the transformation of Europe in the late nineteenth century, the book moves through 1914, the failed peace that followed, the reconstruction of international order after 1945, the exceptional conditions of post-war Europe, the unipolar moment after the Cold War, and the return of harder forms of geopolitical competition.The central question is not whether history is repeating itself. It is what changes when the conditions that once made a political order stable begin to disappear.Russia's invasion of Ukraine, China's rise, NATO, European integration, economic interdependence, energy, technology and strategic autonomy are examined as parts of a wider shift in the relationship between power and institutions.Throughout, the analysis distinguishes explanation from justification and power from principle. Realism is used to keep the constraints of what is visible; liberalism to examine how institutions can make more of what ought to be sustainable.Europe therefore stands at a difficult threshold. The political achievement of replacing much of its internal power politics with law, institutions and cooperation is real. The unresolved question is whether that achievement can remain secure in an international system increasingly shaped by actors that still calculate through power.A precipice is not a prediction of a fall. It is a condition in which the consequences of error increase while the future remains uncertain.