What can we learn from the failed armistice of 1918?
Keeping the peace is sometimes even more difficult than winning a war.
For an enemy to accept defeat, it must be forced to understand why it lost, suffer the consequences of its aggressions — and only then be shown magnanimity and given help to rebuild.
Losers of a war cannot pick and choose when to quit fighting in enemy territory.
Had the Allies continued their offensives in the fall of 1918 and invaded Germany, the peace that followed might have more closely resembled the unconditional surrender and agreements that ended WWII, leading to far more than just 20 years of subsequent European calm.
Deterrence prevents war.
Germany invaded Belgium in 1914 because it was convinced that Britain would not send enough troops to aid its overwhelmed ally, France. Germany also assumed that isolationist America would not intervene.
Unfortunately, the Allies of 1939 later repeated the errors of 1914, and the result was WWII.
Germany currently dominates Europe, just as it did in 1871, 1914, and 1939. European peace is maintained only when Germany channels its enormous energy and talents into economic, not military, dominance. Yet even today, on matters such as illegal immigration, overdue loans, Brexit, and trade surpluses, Germany tends to agitate its allies.