The latest sob story against the use of hydrogen cars is that we don't have the infrastructure built out to refuel them. This sounds plausible until you run the numbers. The beginning of hydrogen infrastructure for travel has to be the highways. Hydrogen cars can go 300 miles between fill ups. If there's a hydrogen station built out every 280 miles, you can take a cross country trip. You're likely to be doing that trip on the interstate highway system so putting a station in for every 280 miles of that system. That system is 47,714 miles long which nets out to 171 stations.
But maybe hydrogen stations are expensive? Individual stations are certainly not cheap with estimates ranging from $500k to $5M per station. Taking the middle point of $2.75M per station a thin national network that would allow national travel via hydrogen would be just under $471M. Actual costs would likely be lower as several efforts are out there to drive down station infrastructure costs.
Getting a full blown national network equivalent to the current gasoline system is unlikely for the simple reason that we're not moving from one mono-fuel situation to another. We're likely to see hydrogen nicely coexisting with electric charging stations and gasoline for quite some time. We don't all have to be fueling up with the same fuel.