One reason why Europe went to war in 1914 is that all of the continental great powers judged it a favorable moment for them to fight, and all were more pessimistic about postponing the fight until later. Not only is this historical paradox an interesting puzzle in its own right, but it sheds light on what is arguably the reigning theory of the causes of wars in general: James Fearon's rational bargaining theory. None of Fearon's three main mechanisms—private information, commitment problems, or indivisibility of stakes—can explain the paradox of the universal, simultaneous view of 1914 as a favorable year for war. Two mechanisms that play a marginal role in his analysis, however—bounded rationality in multidimensional power assessments and attempts to mitigate power shifts through coercive diplomacy—help to explain how Europe's powers became trapped in a choice between war now and war later. These mechanisms were set in motion by background strategic assumptions rooted in the culture of militarism and nationalism that perversely structured the options facing Europe's political leaders in 1914. Whereas Fearon's theory assumes that states are paying equal attention to all relevant information, in 1914 each power's strategic calculations produced disproportionate levels of self-absorption in its own domestic concerns and alliance anxieties.