It would be an overstatement to call this article hopeful, but it’s a good overview of things that could and can be done to draw CO₂ from the atmosphere. The upshot is that the current technological solutions cost too much and do too little. Lower-tech approaches, including planting forests and storing crop residue at the bottom of the ocean, seem to be a better place to start right now.
New technologies may in fact hold the key to the problem. In the second half of the century we should be doing things that we can’t even dream of yet. In the next century, even more so. But it takes time to perfect and scale up new technologies. So it makes sense to barrel ahead with what we can do now, then shift gears as other methods become practical. Merely waiting and hoping is not wise.
Of course, working out how to do it may not even be the hard part.
Even if we try, we are far from guaranteed to succeed … But will we even try? That is more a matter of politics and economics than of science and technology.