The man in the video is ex-American Adam Yahiye Gadahn (formerly Adam Pearlman - go figure), spokesmodel and operative for al Qaeda. If the sound is a little muddy, I suspect they had to keep editing out the sounds of NRA members spontaneously combusting.
The NRA has always opposed keeping guns out of the hands of terrorists, and closing the gun-show loophole.
Why does the NRA hate America? Why are they working with terrorists to destroy our country?
Update: Apparently, Youtube took down the video for violating their terms of service. (And, really, I suppose that telling people to go to gun shows and buy guns to wage jihad should be a violation of their TOS...) Fortunately, it's hosted elsewhere. Crooks and Liars, for instance.