How does Martin Luther King Jr. support his claim that racial segregation is discriminatory and unjust?

Martin Luther King Jr. supports his claim that racial segregation is discriminatory and unjust by emphasizing the moral imperative of equality and the inherent dignity of all individuals. In his "Letter from Birmingham Jail," he argues that segregation dehumanizes both the oppressed and the oppressors, violating fundamental human rights. He also highlights the urgency of addressing inequality, asserting that "injustice anywhere is a threat to justice everywhere." Through these arguments, King underscores that segregation not only perpetuates systemic racism but also contradicts the principles of justice and democracy.