The handbook issued to US soldiers in Britain during WW2 included the line "The British don't know how to make a good cup of coffee. You don't know how to make a good cup of tea. It's an even swap."
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The Canadian province of New Brunswick (which was part of the UK at the time) had a bloodless war with the US state of Maine in 1839
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The flag of the Philippines is flown with the red stripe up in times of war and blue stripe up in times of peace.
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In 1918, after the treaty of Versailles (end of WWI), the French Commander-in-chief said "This is not a peace. It is an Armistice for 20 years." 20 years and 65 days later, WWII happened.
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In 1916, a US amendment was proposed to put all acts of war to a national vote. If you voted yes you would have to register as a volunteer for service in the United States Army.
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