It’s not fantasy. I’m working on a startup to enable this technology. It’s a hard problem, but not impossible. And the energy needs are not as great as you think. A relatively small patch of the Sahara or Gobi desert or open ocean would be sufficient.

You might need to panel over the whole Sahara: https://www.wired.com/story/the-stupendous-energy-cost-of-di...

Much less than the whole Sahara.

its indistinguishable from fantasy extrapolating from the given track record . Previous fantasy technology break through like harbor bosch were viable only "after" major diaasters and worldwars and brought with them ever more destructive hidden costs.

Haber-Bosch predates the world wars.

But was only usefull with free trade guarantees by a sea empire. In colonial empire times it might aswell have been alchemy to make free cheese on the moon.

I am confused. Haber-Bosch was developed to work around the need for free trade guarantees. There was enough nitrates in Chile for the foreseeable future in 1911, but Germany wanted a local source of fertilizer to remove their foreign dependency.