I'd like to take the contrarian view that this isn't true but I'm not sure. I first argued weakly that perhaps we weren't really getting desensitized, that she had a sample size of one looking at herself and her reactions to movies and TV news. But I didn't really believe that argument myself - it seems obvious that if you see all of the Terminator movies you're not going to be shocked by Total Recall. My next ineffective argument was that perhaps video violence serves a useful purpose - that we're less likely to panic the first time we see somebody get in a car accident in real life, and we can respond more effectively. But that argument is actually the opposite of my first argument, assuming that desensitization does happen. Apparently studies have been done but I haven't seen anything particularly convincing either way.
It does occur to me that perhaps desensitization isn't the problem we think it is.
- How broad an effect does desensitization have? If you can watch Lethal Weapon and cheer when Riggs kicks the drug dealer in the nuts and breaks his arm (scene 19C), does this mean you'll cheer when you see somebody do that in the street? Not bloody likely (pun intended). Without the setup of movies, seeing this for real would be terribly upsetting, shocking, and not likely to make you cheer. So maybe desensitization is not that transferrable.
- What effect does desensitization have? Sure, we don't feel so much like vomiting after years of watching gut-churningly violent movies. But does it necessarily make us approve? Or does a movie like The Gift make us consciously condemn the wife-beater even though that role is played by Keanu Reeves?
- How does violent entertainment affect us differently? Surely there are many factors that change how violent entertainment affects us, such as age, upbringing, gender and personality. So I've watched a bunch of Jackie Chan movies, and now I take karate class and love it. I don't think I'm more likely to hurt somebody else now though, except in self-defence, and maybe not even then. Is it only a minute fraction of the population that is more likely to commit violence through exposure to violent entertainment?