With the technology's available today the government could easily force you to drive the limit but that's not what they do. They let you buy cars with top speeds that aren't even close to being legal anywhere in the US then tell you not to use them and ticket you if you do. When the national 55 limit was implemented under Nixon the PA turnpike that was 65MPH for years before the law was enacted had billboards everywhere saying 55 saves lives. Years after the national law was dropped the limit was raised back to 65MPH due to public pressure. Pennsylvania which is also broke like many other states began raising tolls every 6 months hammering commuters that use the road to go to work. The local news reported that the road began actually producing less revenue than when the tolls were lower because drivers started finding alternate routes out of necessity. Several months later the turnpike commission decided to raise the speed limit to 70MPH to lure people back to the highway although that was not the reason stated for the change. No more signs about 55 saves lives. Interstate 95 through Bucks County which is a much safer road is still posted 55MPH but has no tolls. Just a coincidence I guess.
RE: Need for speed. Germany is the place.