A while ago Top Gear did a drive with that outrageously powerful Buguatti Veyron and I posted the vid here on MT. Watching that (even now) I can't even imagine driving that fast. My mind keeps going to the thought "if he twitches the steering wheel wrong just a little bit" he's all over the road and end up as a smear on one of the trees that lines the track. Out in the Utah, Nevada border there's are nice long, 7-8 mile straightaways that people just zip along down at whatever top speed their vehicle can muster. Again just one wrong twitch of the wheel and they're a permanent part of that desert... at least until it's cleaned up.
Now if they had some way of creating a slotted track that would help keep the car ON the road then okay I reckon, provided that the driver doesn't consider this an "auto-drive" and decides to take quick nap. They still gotta be able to apply the brakes at a moment's notice or at least bloody hell slow down.
I'd rather they spent the effort building a long over due bullet-train coast to coast.
No, there's no effort in raising the speed limit but there's a lot more effort keeping abreast of it. More work for police and EMS.
Those who think that the number of accidents will go down, I'm afraid I'm going to have to disagree. Having driven cross country several times ... there aren't really that many GREAT drivers ... especially for those type of speeds. 55-65, yeah people seem to have gotten the hang of it, but I've come across too many who zipped past me and find them 5 miles later off the road or tangled with another vehicle.