Guys, it's not resistance to new things -- it's just that it's not practical.
Hell, in Germany they only have a couple high-speed corridors. The same in France. Italy has Florence-Rome. The rest of the time, those fancy "hi-speed" trains run on regular tracks. Why? 'Cos high-speed tracks are expensive to build. You don't have crossings on them, so every time you hit an intersecting road, you need to build some sort of under/overpass. High-speed tracks are also expensive to maintain.
So your shinkansen, ICE, TGV, Pendolino (aka Eurostar Italia) or whatever only runs at high speed on very few, highly travelled routes between population centers in relatively dense areas.
The only places in the US where such trains would make sense would be Washington D.C. - NYC - Boston and SF-LA. Guess what? The first one has "High-Speed" trains, but not tracks, because there's no place to build them. The second has been talked about for some time, and there's always some super-fancy plan on the books.
The rest of the time, you're talking about several times the length of track for more or less the same number of passengers.
Oh, and I can assure you, if we had super-highspeed trains in the US, the boarding process would be more like the Eurostar under the channel and less like the ICE: Assigned seating, X-ray machines, metal detectors. Just look at the carnage that happened when that German ICE derailed due to poor maintenance practices.