Crime isn't confined to public trans. There's also carjacking--not to mention drivers who think every road is their personal expressway. Then there are those paying more attention to their cell phone chat or texting or eating
their sandwich--or... "oh, was I supposed to be paying attention to the road? I thought that was for other people." And what about road rage?
I take public trans and sure you have to be aware of your surroundings. From experience, I follow a lot of safety procedures--stay near the driver or in the operator's car on a subway train; avoid isolated stations after dark; etc. BUT the benefits--as one poster said, you aren't just going to the garage, starting the car and taking off. You have to do some moving around. And given that I carry a backpack, there's a little strength work in the bargain.
The transit fares, even when hiked, are nowhere near what you pay for parking, gas, etc. I get to work without having fought a lot of traffic, nut case drivers, and other such road stresses. Public trans isn't perfect. I'll admit that it's tempting to opt for a car sometimes. But given the cost and factors cited above, I'm sticking with public trans for now.