If we could build deep undersea cities we would basically have a template to mitigate all climate instability for future (even on land). We have ruined our lan

If we could build deep undersea cities we would basically have a template to mitigate all climate instability for future (even on land). We have ruined our land and air. We have polluted the oceans to an insane level. What makes you think that we'll do a good job with deep undersea cities? We are even polluting space with debris, are we not?