When whites become a minority it will be because there will be no majority. The percentage of the population of Latin American ancestry at that time will be roughly comparable to the percentage of "traditional white" European ancestry--a definition that changes with every generation and used to not include Italians.
This will be a good thing in terms of solving the racism problem because Latinos have the highest out-marriage rate of any ethnic group. Bless their hearts, they marry blacks, Asian-Americans, whites--pick any group--enthusiastically. Their out-marriage rate (50% in the first generation) is much higher than traditional white Americans, and for all the criticism, during my lifetime I've watched us become steadily more blasé about cross-cultural marriages.
The Latino community is a little Melting Pot engine and soon it will be a big Melting Pot engine. Americans will cease being so easily identified by color, as they have more and more children in various shades of tan and brown. That will make it hard to discriminate.