Why do these Japanese Navy officers have a US Navy flag patched on their uniform?

Question

I saw the US flag patched onto Japanese Navy officers, who are describing American aircraft carrier movement to Admiral Nugumo, while his planes were bombing Midway:

Why would Japanese Navy officers have a US Navy flag patched onto their uniform?

Answer 1

They are playing the American fleet commanders in the war games just prior to the actual attack on Midway. Just like when armed forces play war games in the field they will wear two different color arm bands to show what side they are on.