I believe you meant the red scare"" ... it was mass hysteria scare over the spread of communism in the US and the rest of the world
, Antietam was the bloodiest single-day battle in American history with over 23,000 casualties (men listed as killed, wounded, captured or missing) in roughly 12 hours. The battle ended the Confederate invasion of Maryland in 1862 and resulted in a Union victory.
Don’t fall for the links love!