Woe to the statesman who does not seek in these times a case for war that still holds up after the war is over.

The remark warns that a leader who chooses war must be able to justify it not only in the heat of crisis but also under the calmer moral and political scrutiny that follows. It implies that wartime rhetoric, opportunistic pretexts, and short-term strategic gains are insufficient; the true test is whether the cause remains defensible once casualties, destruction, and unintended consequences are fully visible. Attributed to Bismarck—often portrayed as a practitioner of Realpolitik—it is frequently used to underline the tension between strategic calculation and ethical responsibility in statecraft, and to argue for restraint: wars should be entered only for reasons that can withstand postwar judgment by history, citizens, and international opinion.