An Argument in a Resturant

I'm normally pretty good at keeping my cool in public.  This evening I sort of lost it.  There were two couples of older folks (older and I'm 56) chatting in the next booth.  I overheard the usual Progressive crap, never a surprise, around here your either pretty far right or pretty far left, mostly left.

It was when the old man said Wayne LaPierre and the NRA are Terrorists, that I lost it.

This is to the best of my recollection and I'm going to leave things out that didn't really add to the content.   

In a fairly loud voice I asked:  "Are you calling me a terrorist?"
Man: Well LaPierre is.
Me:  Really how do you figure that?
Man: He get's paid $X for every person killed in this country.  (I really don't remember the amount - I was simply too stunned by the idea to really let that sink in.)
Me:  By Who?
Man: By Wal-Mart and by gun companies.
Me:  Really?  The take a count of the dead bodies and send him a check for every one?
Man: Well I'll tell you, He'll get a raise when they manage kill 35,000 in a year.
Me: We are not terrorists, he does not get paid for dead bodies.  Just dividing his salary by the number of people killed doesn't mean he's getting paid by the body and you fucking well know it.
Wife: Well they make laws that keep manufacturers from being sued for defective products.
Me:  Really, Like what?
Man -as they get up to leave:  Like the Remington 870 Semi Automatic Rifle.
Me: The Remington 870 is a 12 guage Pump action shotgun. Your thinking of the Model 700 which is not a Semi Auto, it's a Bolt Action Rifle.  It's also not defective,  So most of your facts are wrong.
Man: It's defective, it kills people.
Me: The rifles in question had either been worn out or modified and were improperly handled.  That's hardly Remingtons fault.

At this point they bailed, with much mumbling.

After a few minutes I'd cooled down enough to go apologize  to the owner who's a friend of mine.  He laughed.  Said he'd put up a sign saying he supported the NRA but it would kill his business - he's right, around here it would.   Because - We are EVIL TERRORISTS

Or maybe they're brainwashed idiots.

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Yeah I have to go with option #2

Honestly, if there had been anyone beside me and them in there at the time, I'd like to think I could keep my cool. But I'm just not sure.