The machine gun was decisive in securing victories for the Allies in WW1, if that's the time period this is focused on.
A couple of weeks before the Battle of New Orleans, the U.S. and British governments had negotiated and signed a peace treaty that put an effective end to the war between the two countries. Given that news from Europe took about a month to reach the U.S., both the U.S. soldiers led by General Andrew Jackson and the Red Coats led by General Sir Edward Pakenham was a pointless confrontation. A few weeks after the resounding U.S. victory (only 13 men were killed on the U.S. side and 285 on the British side), Jackson and his men got news of the peace treaty signed before their feat of arms.
The Scopes Trial reflects the head-on clash between science and religion in the 1920's due to the emerging scientific discoveries at the time, which discredited scriptures from the Bible, causing great uproar between fundamentalists and evolutionists. I hope my answer has come to your help. God bless and have a nice day ahead!
