Autobahn in Germany is hard to compare to anything, anywhere else. They are maintained incredibly well. They are built for high speed (curves are gentle with slight bank and you will not hear a seam slapping the tires between segments).
Then, the driver education is very well thought out and takes quite a long time to complete. That is generally true in Europe.
The U.S., in my opinion, has the worst driver education in the world. It's a joke. Yet the insurance companies and various safety agencies will not move to do anything about it. If they were serious about reducing accidents, then that is where they should start.
Speed only kills when someone makes an error in judgment. Whether the speed is 10 or 100, an error will almost always end up an accident.
I have no problem with high speed myself, but I took high speed driving courses, so I am comfortable with high speed. The typical driver in the U.S., in my opinion, should not be allowed to exceed 45MPH given the training they have. (45 is a magic number, as it is about as slow as most cars can go in the U.S. and reach top gear).
For the good our training does for the driver, we should just hand out the driver licenses in boxes of cereal.
Now England is another world unto itself. Sparks,..I agree with some of what you said, but some of the roads in England are called sidewalks here in the U.S. And what the heck is up with those roundabouts? I got stuck on one in London for almost 35 minutes. Thought I was going to pass out from being dizzy. Being a noob in England, even if you are a good driver, is not for the timid or weak of stomach.