American rails are decidedly low quality. [The accident record is much worse](https://www.nytimes.com/2015/05/21/world/europe/railroads-ar...), and the freight networks spent many years dismantling tracks and electrification to improve the bottom line.

HSR really depends on straight and level right of ways, along with some better signaling equipment and more (complete?) separation with road traffic. China builds a lot of its HSR tracks elevated with lots of tunnels to blast through hills and mountains. Standard track can stand to meander more for less construction costs.