From what I've gotten out of Call of Duty, it isn't just senseless killing. It has historic values.
Also, freedom and liberty? What freedom game regulation destroying? It is already regulated by age groups. It would just be more regulation by enforcing this act. Unless I totally misunderstood you. :p
I do personally feel, though, that game regulation like this needs to be taken upon the hands of the people who buy them and the people who sell them.