How did the implementation of trench warfare affect the course of World War I?

Trench warfare had a massive impact on soldiers as it caused huge amounts of casualties on the battlefield and also caused health problems of the battlefield. Rain flooded trenches making them muddy, clog up weapons and make it hard to move in battle. This caused soldiers to get an infection known as Trench Foot.

the main reason that the constitution did not proclaim all men to be free and equal is because of the issue of slavery.