The interstates are a constant stream of freight trucks. Trucks cause 4x the pollution of trains. Trucks spew tire and brake dust all over the countryside. Most of the maintenance on highways are the result of trucks, and this is paid for by taxpayers.

Trucks are what get goods to their destination. Rail can only get you so close.

Right. For a 3,000 mile journey, 2,998 of those miles can be by rail with the trailer set on a flatcar. The mile in and the last mile the trailer is picked off the flatbed and hooked up to the semi.

In what sense does the US have the best freight rail system in the world? Not trying to be antagonistic, here---just want to know why you think this.

Regarding your other comment ("trucks get the goods where they have to go"): in other countries, such as Switzerland, many buildings (think an Ikea store) are required to be reachable by rail, in which case regional trains can deliver goods to a hub, and then local trains can take goods from the hub to the store. No need for trucks in this case.

The absolute amount of freight moved by rail in the US is insane. But the US is also roughly the size of Europe and is shaped so there are many population centers far from the ocean.

If you remove bulk freight it’s quite a bit of a difference but still massive.

Much of European freight goes by boat and truck without much train.

I don't see how that relates to the US freight system being the best.