On Monday, Illinois Governor Rod Blagojevich signed legislation making it illegal for anyone under 18 to buy or rent video games that contain graphic violence or sexual activity. On Wednesday, Florence Cohen, who bought “Grand Theft Auto: San Andreas” for her 14-year-old grandson, sued the manufacturer because the game contained too much violence and explicit sex. Her lawyer said no parent or grandparent would knowingly buy an adult-only video game for her children.

But that’s exactly what she did. While “GTA:SA” wasn’t rated adults-only at the time she bought it, it was rated M, for mature, meaning it’s only appropriate for players 17 and older. The higher rating AO, for adults only, raises that age limit just one year, to 18 year olds. Either way, Florence shouldn’t have bought the game for her 14-year-old grandson, and she has no one to blame but herself.

We live in the era of Nanny USA, where there’s no personal responsibility, it’s always someone else’s fault, and the government has to step in to take care of us. This is a classic case.

And don’t use Florence’s age as an excuse. Yes, she’s 85 years old and probably unfamiliar with the Grand Theft Auto series. Even though they’re the most popular video games every made, she’s not exactly their target demographic, but that doesn’t let her off the hook. My mother is 81 years old and knows better than to buy something — a video game, a movie, a CD, a book, a magazine — for my 11-year-old daughter without having some idea what the content is and whether it’s suitable for her granddaughter’s eyes and ears.

Incidentally, no law would have stopped Florence’s grandson from getting this game, because even Illinois’ age restriction would have been moot when grandma purchased it and gave it to the kid. It’s the adult who screwed up here, not the retailer, the manufacturer, or the industry.

I don’t even play video games, nor has my daughter shown any particular interest in them yet, but it’s clear that this is part of the continuing war on content providers. Since I am one of those (on the air, in print, and online), stories like this hit home with me.

Once the Illinois law faces a court challenge, it will likely be deemed unconstitutional, as have similar pieces of legislation in other states. More importantly, we don’t need laws like this. We don’t have one that makes it illegal for a 14-year-old to see an R-rated movie — the industry rates and regulates itself pretty well, and from there, it’s up to the parents. There’s no law keeping a 15-year-old from watching some skin flick late at night on Cinemax. However, there should be parents in that house who make sure it’s not happening.

The same should go for all other forms of content, whether on film, DVD, print, the internet, or a video game. Mom and Dad (and Grandma Flo) have to do their jobs — know what your kids are consuming, keep an eye on ratings, monitor the content. Don’t leave it to the legislature to protect your kids, because they’re more interested in their political future than anything else. And that’s what this is really about.

Going after sexy, violent entertainment gains political points with the uptight moral values crowd, which has been wrongly given too much credit recently. They scream that games like GTA make America’s youth more violence-prone, while the facts show that violence among teens in America has actually shown a pronounced decrease over the last several years — at the same time that these games have grown in popularity. Maybe keeping them inside with their hands on the joystick is a good thing.

On the other hand, no politician can say what really needs to be said here — that American parents have to do a better job of taking responsibility for their own children — because that doesn’t get you any votes. But it would be the right thing to do. And it would be a message that’s both Mature and for Adults Only.