There is no reason to bring a pistol to a Town Hall meeting. There is no reason to bring an assault rifle to a Town Hall meeting.
Here are the reasons why not to bring a gun to a political meeting, especially a meeting where the President of the United States is in attendance:
Franklin Delano Roosevelt.
John Fitzgerald Kennedy.
These American presidents were either shot at or killed while serving in office. One nut. One bullet.
It only takes one.