A government state/country issued thing
Manifest Destiny is a term for the attitude prevalent during the 19th century period of American expansion that the United States not only could, but was destined to, stretch from coast to coast. This attitude helped fuel western settlement, Native American removal and war with Mexico.
The colonial policies and practices that played a part in peaceful or violent transitions to self-rule were very complex. One major one which had a very important role here was Apartheid. This was an important policy which had at its core racial segregation between black and white people.