Well, the transportation professor Sir David King (not me! There are a lot of us David Kings in transportation. We should get our own conference.) argues for dirigibles. Blimps are slow, but for goods that are not perishable this may be an environmentally sound alternative even if we don't build HSR. Here are some highlights from the Guardian:
Airships would be too slow for some high-speed airfreight, and would not be needed to carry the majority of cargo for which much slower ships are suitable. But with a speed of 125kph (78mph), and much lower fuel costs, plus a carrying capacity potentially many times that of a standard Boeing 747 plane, blimps could in future carry much of current air freight.
A recent report on mobility by the Smith School, for example, quoted an estimate by one developer, UK-owned SkyCat, that it could carry twice the weight of strawberries from Spain to the UK of a standard cargo plane, with a 90% reduction in greenhouse gas emissions, much of which is from avoiding the huge fuel burn a jet engine uses to take off.
Other benefits included the possibility that airships would not need to use airports if they were fitted with "lifts" to pick up and land cargo. This in turn would reduce the need for trucking goods to and from transport hubs, and allow less well-connected areas, perhaps in inland Africa, to take part in international trade, said King. For the same reasons the blimps could also be used to reach devastated areas in need of humanitarian aid, he said.