Take quick look at how people drive today. Make it fast though. You may be killed by someone who's busy texting "LOL". Because they're both driving, and stuck in conversation, with nothing else to say.
Obviously... wait, are you still alive? Good. As I was saying, there must be something else behind the decline in our collective ability to drive. Something beyond the obvious explanations like texting, drinking, fiddling with the radio, and joining the 55 mph club. There is too much bad driving out there to place all of the blame on those few things. There must be a hidden culprit out there.
Then it hit me, what about the road tests done by the DMV! You know, the one you have to pass, in order to get a license? Aha, I can blame the government! Think about it. We blindly trust the DMV to test people's ability to drive, when they have trouble simply managing the lines at their facilities. Then we wonder why so few drivers know what to do at a 4-way stop sign, when there is only one other car. Behind them.
There must be a way to make these tests more difficult. Obviously, it isn't hard enough now. Either it's gotten easier, I was a lot dumber when I was tested, or there's some way for idiots to pass without learning anything even remotely related to driving. For added proof, go for a drive on your favorite major highway, around 5 p.m.
Note: If you live in a state that has more silos than buildings with 3+ floors, this may involve traveling some distance.