Hydrogen is also made from water using either solar or wind powered electrolysis. This process has gotten a lot cheaper over the course of the fall. The hydrogen and a fuel cell provide zero emissions power. The US military is also developing solar "blankets" that can be employed in combat zones to power communications and other gear. They could also be used to produce hydrogen if a water source is available. I don't think Obama had much to do with this project. Fuel cells are environmentally friendly yes but they also enormously increase the survivability of front line troops. If you want stealth transportation fuel cells of batteries are your only options.