The bill of rights play a role today, in that people living in the US are given rights such as the freedom of speech, assembly, religion, etc, and that the government should not try to interfere with a person living in the US's belief unless it starts to hurt other people. Without it, our citizens would not have been part of a democratic nation, and it would not have had a right to voice and do what they want (that is, while it is under the law)
hope this helps