How Guns Are Just Like Cars
I agree that cars and guns are a great analogy, for several reasons.
First, a drunk driver chose to get drunk and get in the car. That's why cars for folks we believe will drive drunk can have ignition locks. Background checks, waiting periods, trigger locks, mandatory training, registration, and a more robust mental health system are firearms' equivalent of ignition locks. Second, we don't allow non-roadworthy vehicles like tanks or monster trucks to drive on our freeways. That's the equivalent of an assault weapons ban. Third, stop signs and driver's licenses don't mean the government is coming for our cars, and gun safety laws don't mean they're coming for our guns. Fourth, responsible car owners don't need all the laws we have. But we have them anyway, because it's important to keep irresponsible folks in check as much as we can, for the sake of the rest of us.
Indeed, I can only think of one major difference between guns and cars. Guns were designed for one purpose and one purpose only: Injury, often to the point of death. Maybe that's a deer in the woods, an enemy soldier in war, a criminal in your house, or a thug on the street, but it's always injury. Vehicles are obviously intended for a different purpose.
Guns don't kill people - people with guns kill people. People with knives do too, but not nearly as many, as evidenced by the knife massacre in China that injured over 20 people the same day the Sandy Hook gun massacre killed over 20. We can't kid ourselves; the guns do make a difference.
For more, I recommend this Ezra Klein article, "Twelve Facts About Guns and Mass Shootings in the United States." http://www.washingtonpost.com/blogs/wonkblog/wp/2012/12/14/nine-facts-about-guns-and-mass-shootings-in-the-united-states/