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

https://caidenouzp991.scriblorax.com/posts/a-closer-look-at-the-most-iconic-civil-war-flags-of-the-era

The Union flag, often called the Stars and Stripes, symbolized cohesion and patriotism, that includes 13 stripes and a field of blue with stars that represented both kingdom within the union.