Why are we so worried that terrorists will manage to reach the US and pass through the vetting system when we have gun massacres committed by US citizens every day. How many foreign terrorists have killed on US soil since 9/11? And yet we have massacres in school and churches and theaters all the time. We react and huff and puff but we do nothing about the hundreds of thousands of guns available. Anyone can buy one. Go to a gun show and there's no checking or waiting. We snarl and gnash our teeth about what's happening in Paris, a city I love and have visited many times, but we lose the same number of people here in a month or less.
No, not anyone can buy a gun. You have to
Be 18 for a long gun (rifle or shotgun)
Be 21 for a handgun and in your home state
Not have a felony or domestic violence record
Never have been adjudicated to be mentally incompetent
Not be addicted to drugs
Never have received a Bad Conduct Discharge
Never have renounced your citizenship
And those are just the federal laws. Your state may have more, such as Illinois or California.
Some states allow a face-to-face transfer without a background check (the so-called Gun Show Loophole that was specifically written into the law), but some don't. But buy from a dealer anywhere, even gun shows, and you WILL get a NICS background check.
And then there're the whole transporting guns, carrying guns, licensing, permits, and the like that go on at the state level.
While we're on the subject, more people die from doctors' mistake than die by guns every year. (30,000 gun deaths, mostly criminals killing criminals vs. 100,000 doctor deaths) Before we tackle the scourge of gun violence, shouldn't we tackle the problem of incompetent physicians?
If it saves just one life.