The main tradition and rule of British foreign policy during the last 500 years: not letting any European nation become dominant in the continent, because, once achieved that, outersea expansion follows, treathening British interests.

Felipe II, Louis XIV, Louis XV, Napoléon I, Wilhelm II and Hitler got a taste of it.

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"War is less costly than servitude, the choice is always between Verdun and Dachau." - Jean Dutourd, French veteran of both world wars

"A mon fils: depuis que tes yeux sont fermes les miens n’ont cessé de pleurir." - Mère française, Verdun