Trump says, "Make America great again," but when was America ever great?

Was America great when Europeans crossed the Atlantic Ocean and took the Natives' land and proclaimed it as theirs?

Was America great as they took that land and banished the true Americans onto what we called "Reservations,"

which are barely existent in today's time?

Was America great when the so called "Americans" went to Africa to fetch people to do work for them.

The work that their people were deemed too "superior" to do?

Was America great as these white men they liked to call Americans bought and sold other human beings for a profit with little to no concern for their wellbeing?

Was America great during World War II as "Americans" dropped the nuclear bombs onto Japanese cities killing over 200,000 innocent civilians?

Was America great as we forced our people, Americans, into internment camps strictly due to the country of their origin?

Was America great as police hosed down blacks in the city streets as they were protesting for equal rights because they were American?

So when Trump says, "Make America great again," I would like to know what time he's referring to,

because as you can see America's history is far from great and I wouldn't like for that to be ignored.