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

https://remingtonfseq702.stonefielddigest.com/posts/from-battlefields-to-museums-the-journey-of-historic-civil-war-flags

The Union flag, is called the Stars and Stripes, symbolized team spirit and patriotism, presenting thirteen stripes and a field of blue with stars that represented every kingdom within the union.