So Pessimistic. The earths electrical power supply, could easily be generated from solar, generated in the worlds deserts. It just takes a change in the economy of wealthy nations caused by perhaps global sea level rises or more likely perhaps running out of oil and gas. If it is in a countries national interests, said countries might invest in solar in the worlds deserts, and might help to stabilize unstable areas.
Optimistically: Politicians globally might agree that global warming is caused by the burning of fossil fuels releasing CO2, and do something before the fossil fuels are all used up. In the present climate of denial, by some elected leaders, this is unlikely.
Solar power generation does not have to be about building walls but it could be a start and bring down the cost of solar generation However it is probably better to place solar panels where the neighbours are not going to throw stones at them.
Edit link https://solarlove.or...d-solar-energy/
I'm just looking at the chances of this type of energy-intensive CO2 removal technology versus its competitors, such as CCS, reforestation etc.
I really do not think a scheme that relies on putting back 100% of the energy originally obtained from fossil fuel burning is going to make the cut, when there are other options.
The tide is turning on fossil fuel, that will happen. Just look at the turmoil in the automative market today. The shift to electric seems unstoppable. A few dinosaurs like Trump won't hold back that tide. But it will be a very long time before we have so much renewable energy, if we ever do, that we can afford reduction of carbon to elemental form as a solution to our CO2 problem. We have other methods.
What we have to watch, I think, is the new economy of batteries. There are already looming problems (pollution, child exploitation, corruption, geopolitics) associated with extraction of elements for battery manufacture. We need to start focusing the international community on some of this before it breeds new monsters.