There are over 400 million privately owned guns in the United States.
http://gunwatch.blogspot.com.au/2018/02/trump-era-nics-gun-checks-2018-starts.html
“There are over 400 million privately owned guns in the United States.”
And how often to you suspect those firearms are used by citizens in legal, self-defense situations to prevent or stop a violent crime? (Hint: over 80000 times per year!) What does the DoJ have to say about that?