I say that all opinions are welcome as long as they are informed.
The Army and police force represent the State/government. It is believed, considering the way the country was founded, the writers of the Constitution had a fear of government and wanted the people to be able to arm themselves in case government got out of hand. However I do not believe that the Founding Fathers would think that assault rifles were a good thing in the hands of looneys and mass public shootings.
But instead of questioning the levels of mass public shootings, the NRA and proponents of the NRA think the ability to own large magazine assault rifles is a right guaranteed by the U.S. Constitution to a point that the type of collateral damage we have been seeing in the U.S. is an unfortunate, but necessary to guarantee this right. Most reasonable people, even NRA members would question this. NRA leadership stands apart from the definition of "reasonable" when it comes to guns.