In the song "brother, can you spare a dime? " where did “half a million boots go sloggin’ through hell? ”

"Brother Can You Spare a Dime?" was a heartfelt anthem full of questioning and anger, written during the Great Depression.  Lyric writer E.Y. Harburg and composer Jay Gorney wrote the song in 1932.  It looked back on where Americans had been before the stock market crash of 1929.  One of those places, where "half a million boots went sloggin' through hell," was through the trenches and battlefields of World War I.   America had thought it was in great times after that war, during the roaring '20s.  But then everything came crashing down and minds and hearts were depressed as much as the country was in Depression.  The songwriters captured that feeling well, and the song resonated with people across the country.