The official observances in France, were under rain. Indeed, the rains were heavy enough to repeatedly interfere with the satellite TV transmission signal back to C-SPAN. You see that in the multi-national ceremony and in President Trump’s address at a war memorial for Americans. The rain, and the disruption, is so appropriate to the commemoration of a war in which men lived in muddy trenches, never really dry, for years. Feet, constantly wet, started disintegrating. It was called “trench foot” and is called “immersion foot syndrome.” [Emphasis added.]
Trench foot, or immersion foot syndrome, is a serious condition that results from your feet being wet for too long. The condition first became known during World War I, when soldiers got trench foot from fighting in cold, wet conditions in trenches without the extra socks or boots to help keep their feet dry.