The Union flag, is called the Stars and Stripes, symbolized cohesion and patriotism

https://simonadmb548.valiantfield.com/posts/the-role-of-civil-war-flags-in-battles-and-ceremonies-2

The Union flag, called the Stars and Stripes, symbolized cohesion and patriotism, providing 13 stripes and a subject of blue with stars that represented every single nation inside the union.