The US has one of the best and most comprehensive railways on earth. The problem is that its a freight railway that passenger trains have to work around. In southern california the metrolink regional railways link the entire region, but take second fiddle to freight rail which kneecaps their utility unless you are working 9-5 in downtown LA. The entire network is tailored for that commute because thats the best they could do with the freight rail schedule. We need grade separation between freight and passenger trains before any regional or national network will ever improve, and amtrak and other agencies like metrolink have no money allocated for this.
