Springfield 1903 rifles have been used until the Battle of Guadalcanal, which is normal. As for the helmet, it is normal to be an English helmet during World War I.

After World War I, the United States greatly disarmed, with fewer troops and less military expenditure, and used a lot of sealed materials during World War I.

As for the cowboy hat, it was the standard of the American army in tropical and subtropical areas at that time, and the Pearl Harbor Army also had one.