Who was used as labor to build structures and used in psychological warfare?

Psychological warfare involves the planned use of propaganda and other psychological operations to influence the opinions, emotions, attitudes, and behavior of opposition groups. RAND has studied military information support operations (MISO) in many countries and war zones and has provided objective and supportable recommendations to policymakers on methods and tactics to employ or defend against these operations.

the difference is that white collar worker performs skills like worker as a scientist or well blue collars do physical work and they do services like being a cook.

in 1897, pershing became a tactical officer at west point, and that's where he was given the nickname "black jack." pershing's first name is "john," for which "jack" is a nickname, and he was a white man who commanded black troops. hence "black jack".