The economic unions are made with the purpose of enabling two or more countries to be able to trade between each other with ease and without restrictions and problems. The labor force to be able to move freely in each of them, if there's need for it of course, as well as the free movement of capital, and free movement of goods. These things are all made in a way that they will be well suited for each member of the economic union, and that it will enable the economy of each member to improve.
In 1968, during the Democratic National Convention held in Chicago, governors gathered to discuss, once again, the future of the U.S. involvement in the Vietnam War.
There were two opposing groups. On the one hand, the ones who didn't want the U.S. to continue participating in the War, led by Eugene McCarthy. On the oher hand, the winning side, who supported the war, led by Hubert Humphrey.
As a result, that same day outside the Convention, thousands of antiwar activists gathered to protest and to show their respect for McCarthy. But they were not alone, because Richard Dale, who was the Major of Chicago by then, deployed thousands of police officers to alleviate the situation. The event ended up in a complete disaster: people beating each other and getting hurt. Therefore, this episode is also known as "the Battle of Michigan"