The sinking of Lusitania in 1915 which would eventually lead to the German forces stopping submarine patrol to keep the United States neutral. In 1917 German than started submarine patrol once again and the result was the United States entering the war. These were some of the key events in which new technology and weapons were deployed. The main changes in warfare is that the advancements created more destruction, more death, and made the daily lives of soldiers living in the trenches horrific. These events would lay the foundation on how future wars would be fought and how the extent of destruction would be decreased as weapons and technology further