piongain, if we invest enough in solar panels and wind turbines, we could get nearly unlimited "free" electricity (if we disregard the cost and the resources needed to build the panels and turbines and maintain them). The same could theoretically be said of wave energy and tidal energy, though the costs per energy unit are much higher AFAIK. Note solar panels could be placed in deserts where the land is quite useless for agriculture or forest or habitat, and wind turbines can be offshore and even floating.
With unlimited electricity, surely there are many ways to pull down CO2 from the atmosphere and sequester it. So yes, our hope lies in changing people's minds, and then the physics would be on our side.
Unfortunately, that hope is quite remote, given the limited time we have and the large number of people that need convincing. But it's not physically hopeless.