IMO, gun ownership is not as important. It's what number or percentage of Americans support the Second Amendment. This, I think, is something that the gun control people ignore. You'll see things like:
"The NRA only has four million members. They can't be that
powerful. Four million is a tiny percentage of the 300+ million Americans in this country. The NRA is just a very vocal minority and a lobbying arm of the gun industry."
"Gun ownership is on the decline. Fewer Americans own guns today than before, therefore the gun lobby's days are numbered."
I think both are flawed for a few reasons:
1) I made this point in another thread, but I'll make it here too: the NRA's influence does not reside solely with those who are members. It also has the ear of many more non-members. It thus represents a large swath of Americans.
2) The gun control people seem to forget this point, but the number of people who own guns is not the same as the number of people who support the Second Amendment. There are plenty of people who don't own a gun, have never owned a gun, probably never will own a gun, and who don't know that much about guns, but who nevertheless strongly believe in and support the Second Amendment. They appreciate that they have the right to acquire a firearm should they feel they really need or want one.
In the past, even with higher levels of gun ownership, it seems fewer Americans supported the Second Amendment. A lot of the gun ownership was among hunters, and hence the gun control proponents could always rely on the, "We're not trying to take away your bolt-action hunting rifle or anything like that..." and thus the constant drum about hunting and so forth. Joe Biden said recently about how one problem for them was that they are not dealing with just hunters anymore, they are dealing with a lot of people who own guns for protection and sport shooting purposes.
We see this also with the Anheuser Busch guy withdrawing his NRA membership, saying how it "used" to be an organization of hunters and how he sees "assault weapons" and "high-capacity magazines" as bad. He was the ideal type that the gun control people would target. Basically people who had the attitude of, "It's fine if you take away THAT guy's gun, just so long as you don't take away MY gun."
Now there has been much handwringing by the gun control people over how the Second Amendment is now seen as an individual right. Many of them really think that it was a collective right because they don't know the history of it. And for many years, I think this was sort of the standard line-of-thinking, that the Second Amendment was just a collective right and most people who owned guns owned them more for hunting and so forth, and thus gun control was much easier to pass.
But since the 1960s, gun rights people have fought hard to get people to understand what the Second Amendment is really about, that it protects a right to keep arms for self-defense (which can include the government, although that can require more in-depth explaining or else you can get portrayed as a conspiracy theory type) and that terms like "assault weapon" and "high-capacity magazine" are political terms meant to trick the general public.
As long as the general public believes in the Second Amendment, then gun ownership levels are not as relevant, but what is important is that gun rights people continue to fight vigilantly to keep the general public educated on firearms. For example, some people, maybe even a lot, who support the Second Amendment, only recently since the Newtown shooting became aware that the AR-15 is not an automatic fire weapon, that it's semiautomatic. Beforehand, they supported the Second Amendment, but otherwise only had a passing interest in firearms.
I thought a textbook example of this was the conservative Bill Kristol. I saw him on television some months back say (paraphrasing as I forget the exact quote): "I support the Second Amendment, but I'm not sure if I support someone being allowed to own a semiautomatic, quasi-machine gun that shoots five-hundred rounds in an instant." (
). However, now he is aware that AR-15s are semiautomatic, so he was one who supports the 2nd, but didn't know much about guns, and now has educated himself more on the issue.