• Hydrogen is not sustainable while electric power could be used for other things. Only when there is a massive excess of renewables(+Batteries) this becomes remotely viable.

    • You can’t exactly use electricity directly to power a rocket, and fuel represents such a small cost compared to everything else that governments can afford the dedicated production.

      Honestly though, the spacecraft themselves are such a tiny emitter compared to things like manufacturing, transport, and electrical generation that they can basically be ignored untill we have basically eliminated thouse emissions.