So that everyone knew there were Jewish I think
They took the place of men in many war industries
They didn't. At the time that Jesus lived the Romans had very little dealings with him. In fact they didn't even know who he was. That's why when it came time to arrest Jesus they had to have someone (Judas) point him out. It was only a certain group of Jewish authorities who perceived Jesus as a threat and so acted against him.
An amendment to the Constitution must be approved by 3/4 of the states (A). That's why it's so difficult for an amendment to be ratified.