I agree entirely. It is not a mistake, however. It is based upon the business case of the revenue that speed enforcement generates. Some police chiefs will actually admit this.
The newest fad is to install automatic semaphore (traffic light) monitoring equipment similar to photo radar. The idea is that vehicles running reds will be photographed and sent a ticket. One may argue that red light running is a bad idea, and I agree, but most of the tickets issued are in the first few tenths of a second after the yellow->red change. It's pure business case. As a matter of fact, the monitoring equipment is given to jurisdictions *free* from the manufacturer -- who gets a share of the ticket proceeds.
It's business. It has nothing to do with safety. Safety is just the cover story. Just a small scale version of the WMD/Iraq manipulation that you're fond of discussing.
If there was a sincere interest in red light saftey, they would just put a 1.5-2 sec delay from the red one way to the green the other. Some jurisdictions do exactly that.
Someone else in this thread mentioned that the speed limits used to be much higher. It seems to me that the speed limits are nowabout what they were in the 1960's (after a ridiculous 20 or so years at 55mph). However, car technology is vastly improved and an average consumer sedan can go 100mph safely all day long.
The one argument that supports lower speed limits is the horrendous congestion in most American cities. Too bad they haven't been spending that ticket money on improvements to the infrastructure...