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If you want to muck with France during/after WW1, your best bet is to do with via the brief civil war that occurred after the Franco-Prussian War in 1871.

Another interesting thing might be to have the US refuse to acknowledge the Treaty of Versailles and threaten to declare war on France unless a treaty that follows the principals that they outlined for ending the war. Given that the US had troops in France at the time it should be very real threat, especially if Britain public supports them.

Another is to have the US react to the French and Belgian troops entering the demilitarized Rhineland in 1921