"The guard is retreating!". At least in the poetic account by Victor Hugo, which is every-schoolboy-knows stuff in France, the incredulous cry that arose from the ranks of the French troops at Waterloo after the last-chance attack by the Imperial Guard on the Allied centre had been beaten back; the signal that the battle was lost and the trigger for Napoleon's army to break and flee the field. By analogy, a general exclamation that all is lost.