I didn't really find it to be anti-gun at all.
Yes, it carried a message, but it wasn't anti-second amendment rights. I got the impression that it was anti-war/poverty/destruction and definitely anti-dealing with tin-horn dictators.
I think one of the characters even made the point that if they didn't sell the weapons, the bad guys would just find another way to kill each other.
I have to admit, I was kind of sad when Bilbo Baggings took a slug to the head.