Final answer:
The correct answer is option 2. The Vietnam War highlighted the irony of African American and white soldiers fighting and dying together for a nation that still practiced segregation.
Step-by-step explanation:
The best summary of Martin Luther King Jr.'s statement about the Vietnam War is that the war highlighted the irony of African American and white soldiers fighting and dying together for a nation that still practiced segregation.
This statement acknowledges the disproportionate number of African American soldiers who fought and died in the war and the racial tensions that existed both at home and on the battlefield. It emphasizes the need for equality and integration in the armed forces and critiques the lack of progress in achieving racial harmony.