We aren’t locked in for the next twenty years, only the next ten years.
We could build a thousand RBMK like nuclear reactors in a decade and then suck out 50 ppm of CO2 out of the atmosphere in another decade.
Would cost $500B to $1T or so.
We just don’t really think global warming is serious enough to warrant an action plan at the scale of the Manhattan project, Apollo program or Messmer plan.