The Union flag, is known as the Stars and Stripes, symbolized solidarity and patriotism

https://landenfwmq676.alderbrief.com/posts/a-closer-look-at-the-most-iconic-civil-war-flags-of-the-era

The Union flag, generally known as the Stars and Stripes, symbolized cohesion and patriotism, proposing 13 stripes and a container of blue with stars that represented both kingdom within the union.