<human>:  Why did the Union lose at the Battle of Chattanooga?
<bot>: The Union lost because the Confederates had more men and better weapons. The Union had a force of roughly 11,000 soldiers, while the Confederates had more than 25,000 soldiers. The Union also had only about 1,000 horses, while the Confederates had about 4,000. Finally, the Union had a small number of cannons, while the Confederates had many more cannons.