What three pieces of evidence support the idea that many americans did not or should not have supported the american war effort in world war 1

All I would know on this matter, is : America joined WWI because of the American lives being lost on Passenger liners such as the RMS Lusitania. 

The  pan-african movement  was an "emotional, cultural, psychological and ideological  movement  that began among the  african  dispora in the western hemisphere, for a closer  purpose, so that  african  people could feel secure, attain political, economic as well as psychological power visa vis other races or world regions" .