Um, I defy the OP to establish how to set a speed limit that will be strictly enforced. The reason speed limits are not obeyed isn’t because they are so low. This is amply demonstrated by the fact that, back when the national speed limit on highways was 55, there wasn’t really any significantly larger number of people who “sped” than there are now, with speed limits that go as high as 75 in many places. Drive through Nebraska, for example, on the I-80, at 75 mph, and you’ll be passed regularly, pass almost no car, and be quite convinced you could do 80 and be in no trouble.
So no matter what limit you set, people will drive faster than the limit, unless you set the limit so high that it no longer limits people because they will drive slower for safety reasons.
Second, I defy to OP to support with statistics the claim that, in Knoxville (or anywhere else for that matter), speed is not a primary cause of accidents on the highways/freeways. Speed, according to most experts, is always the #1 cause of accidents, if not the sole cause, then the main contributing factor. Speed shortens accident-avoidance reaction times, decreases the ability of the car to handle (by reducing the ability of friction between the tires and the road to overcome the inertia of forward momentum), and increases the force of impact when accidents occur. As a nation, accident statistics almost always go up when speed limits are increased, as one would expect. We would ALWAYS be safer if we went slower as a whole.
Thirdly, contrary to the assertion in the OP, failure to obey the law is immoral, with the sole possible exception being when one can articulate a reason why the law in question is itself amoral (such as refusing to get off a “white’s only” bus in the 50’s). When you live in a society, you are accepting as a benefit of that society the advantages we obtain through cooperation and sharing. In return, we must be willing to abide by the rules that society sets, else those benefits will disappear. A society that ignores its laws becomes lawless; a lawless society loses many of the advantages of being a society. Thus, moral behavior includes respecting the dictates of the society in which you choose to live.
So, then, why the trouble? Because most drivers do not view speed limits as morally necessary. Much like tax laws, copyright issues, and other such legal areas where we do not routinely see or think about a class of “victims,” drivers don’t think of speed limits as something that protects themselves, or society as a whole. Instead, they view speed limits as personal limitations existing for no particularly important reason. Thus, when driving to work in the morning, or home at night, or to the beach for the day, or just to the store for some milk, it doesn’t seem very crucial that my speed be matched to some seemingly arbitrary limit. It’s far more important that I complete my journey quickly. If I give the limit thought, it’s solely because I am worried that that curve ahead may hide an officer of the law, who might nail me for my failure to obey the law. Note that most people don’t keep themselves from killing people, or stealing from banks, on the basis that they are worried about being caught.
It’s not clear if this is a particularly American or Euro-American thing. I do know that, when living in relatively rural California, if I found myself behind a driver going slower than the limit, that driver was often hispanic. This seems to have tied in with a somewhat more laid-back lifestyle, in which go go go was not so important. Similarly, in urban California, slower drivers on the freeways were often Asian appearing, which, again, seemed to tie in with a generally more “careful” approach to life in general, in which rules are more respected. So the whole break the speed limit thing may be a reflection at some level of our own, cultural tendencies, which are well known to be viewed by many in the world as fast-paced and self-thinking.
In short, changing the limits has no really important impact on the tendency to speed; people speed whatever the limit. Speed DOES kill, maim, etc.; that is, it is a major contributory factor in most accidents, as well as in the severity of the injuries suffered in the accidents. Moral people should view speed limits, like any other law, as important to follow, but do not, perhaps because they don’t equate these laws with some morally important behavior (there was no eleventh commandment stating, Thou shalt not to to fast). In any event, whether culturally related or not, speed limits in America are always going to be “ingnored” the same way they currently are, and short of creating some sort of vastly better method for determining who is speeding, and punishing them for it, it’s unlikely to change.