My understanding of fuel cells is that, at least early on, they had a problem with hydro-carbon based sources of hydrogen, of getting clogged up (contaminated). Maybe that isn't the case with 'pure' hydrogen? There are other problems such as the heat generated and that they need to warm up before they are efficient. They do not work well with the typical cycle of jump in the car and take off, drive ten minutes and then shut down? Japan is a lot smaller than the USA, so it will take a lot less time to create any infrastructure needed for any alternative fuel/energy. There are batteries that work somewhat similar to fuel cells in that the electrolyte is replenished to recharge them. The electrolyte is held in a tank separate from the battery and when exhausted it can be removed and then refilled with recharged electrolyte. The exhausted electrolyte can be recycled by being recharged. This allows the vehicle to be "refueled" almost as fast as a petroleum based vehicle. The future is electric - whether the electricity comes from a battery or a fuel cell remains to be seen.