First of all I hate your thread title. How is it ever necessary to have the right to believe something? People are capable of believing at least three impossible things before breakfast. And they will do so with or without rights.
Second, there are very few atheists who think they have proven there are no gods.
Second, there are very few atheists who think they have proven there are no gods.
If there is a god, I want to believe that there is a god. If there is not a god, I want to believe that there is no god.