Why did World War 2 temporarily break down racial barriers at home?

The war industry needed hundreds of thousands of workers. So they hired both genders and all races. Many of the whites learned to make friends with their fellow workers and to learn about their cultural ways. The tragic part was that it was only temporary. The women seemed to accept them better and not carry on so many racial grudges later but the men seemed to harbor strong feelings during the war and after the war. The problem was not even begun to be resolved until the Civil Rights Act in the 1960s. Another factor was the community effort to support the war with war bonds, Red Cross projects and other events. The different races would mix to roll bandages, collect metal and other items and to help the wounded in the hospital. I don't know if this was true in the south but it was in the north and the west.