<span>The U.S mail cars were connected to the Pullman cars so they could allow federal intervention to end the strike by letting railroad executives to claim the strike interfered with the mail.</span>
The Supreme Court upheld the policy of interning Japanese American citizens during World War II.
After the Japanese attack on Pearl Harbor, the US officially declared war on Japan. Shortly after this, the federal government was suspicious of Japanese American citizens and feared that many of them were spies for Japan. This is why president Franklin D. Roosevelt passed executive order 9066. This law resulted in the placing of Japanese American citizens into internment camps.
Korematsu was one of those citizens placed into an internment camp. He lated sued the federal government saying that this was a violation of his constitutional rights. However, the Supreme Court sided with the government as they felt that wartime actions can justify actions like the one taken by president Franklin D. Roosevelt.
It was the Declaration of Independence I think