There is no "Battle over the Right to Bear Arms in America". There is a battle over effective gun regulations. We have no effective gun regulations in the United States at the present time.
Mr. Hemenway did not push his books. They were not even mentioned in the show.
My personal opinion is that universal background checks of gun sales of ALL types would be the most effective legislation. Manufactures should also be required to use some type of firearm microstamping.
Thirty round magazines have no use other than to kill large numbers of people very quickly.
50 cal. sniper rifles are for sale in nearly every gun shop in the USA. They have no use as a sporting rifle. They are for killing people at very long ranges and disabling vehicle armor at shorter ranges.
Glock pistols carried by police usually carry up to 17 rounds. But 30 round magazines are only for killing large numbers of people quickly.
The NRA appears to favor gun and ammunition sales of all types including straw sales to criminals, gun runners, milita groups and white supremacists. The NRA represents firearm and ammunition corporations, not people.