Without debating the economics of the California project, it's
worth noting that European railroads are building much longer
tunnels and investing lots of money in new infrastructure.
(This is noted at the end of the SJ Mercury article.) The new
European tunnels are all intended to carry both fast passenger
and freight trains, as is the case with the Channel Tunnel
(Chunnel).

There are any number of locations where U.S. FREIGHT railroads could
use new tunnels to avaoid problematic grades and operating
inefficiencies. The problem is that even the biggest freight
railroads would have problems financing such new tunnels (or
major new bridges) as these would have to be ammortized over many
years, and these businesses are primarily focused on short-time
returns.

On the other hand, one of the German dedicated ICE high-speed lines has
grades over four per cent, which are managed just fine with electric
propulsion.

-- Ernest