January 21 in Military History — On This Day

⚔️📍 Place de la Révolution, Paris, France1793

King Louis XVI Executed by Guillotine

King Louis XVI was guillotined before a large crowd in Paris after being convicted of treason by the National Convention. His last words were cut off by a drumroll as he tried to proclaim his innocence.

The execution of a king sent shockwaves across Europe, hardening foreign opposition to Revolutionary France and igniting the wars that would consume a generation.

Outcome

Monarchy abolished; European monarchies unite against France

Siege of Khe Sanh

NVA forces besieged a US Marine base near the DMZ in the mountains near the Laotian border. Westmoreland, fearing another Dien Bien Phu, poured resources into holding it. As the world watched the siege, Giap launched the Tet Offensive against South Vietnam's cities — Khe Sanh had been the feint all along. The Marines held Khe Sanh, then abandoned it four months later.

The siege fixed American attention while Tet unfolded. The decision to later abandon Khe Sanh — after holding it at enormous cost — was a propaganda disaster. 'If we're not in Khe Sanh to stay, why did so many men die there?' It became a symbol of the war's strategic incoherence.

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