It can be easy to become desensitised to Call of Duty's brand of realistic-yet-cartoonish violence. As motion-captured video game dudes blow each other away over and over again, whatever I'd normally feel at watching that kind of carnage melts away. I see the game for what it is, and it stops having an impact.
Videos like this one, a live-action recreation of the game by Aperture VFX, can be an odd reminder of just how violent Black Ops 2 is. It's very well-made, and I was impressed by how realistically they managed to re-create the first-person killing of Black Ops 2. But it's also a reminder that, yeah, in this game you pretty much just horribly murder your friends over and over. And laugh about it!