Why did america wait to end segregation until after mlk's death?

The US passed the civil rights act and the voting act in 1964. That was when they seriously began desegregating "whites only" public schools in the south. That was promoted by President Lynden Johnson, a democrat. All of the southern states at that time were Democrat and they were so outraged at Johnson's action toward equal treatment of black people that every one of them switched parties and became Republican. At that point sympathies toward African Americans discontinued in the Republican party and was picked up by the Democratic party. That took place, however, around 1964, four years prior to MLK's assassination.

Segregation shouldn't have ended.

The Young think that 75 years is ancient history. I'm just saying that merely 75 years before I was born, it was still legal in these United States to own human beings as slaves. Things have changed dramatically for the better since I was a young person.

Because DemoKKKrats kept voting for segregation.  The top 10 most segregated schools are currently in blue states. 

Johnson was in the process of doing so a year before MLK died