It's not gonna be cheap. Building walls around Miami, L.A., NYC, etc, will be very expensive.

The mass refugee problem from other nations will be a challenge. If LM is screaming about migrants now...just wait. I think 1/3 of Bangladesh will be underwater (at least at high tide) by the end of the century.

It's gonna be a mess, and our grandchildren will curse us.

Who knows?

After all, very few of us are going around cursing the Industrial Revolution. Many of us grateful that our world has a vastly better standard of living and technological level than it would have had if our forebears had refrained from polluting the world and burning fossil fuels. The hardships that would need to be borne to prevent climate change altogether - even to limit us to 1.5C - would be severe and significant. Our grandchildren may be perfectly fine with the choices we make today.

Especially if we use the metaphorical "us" - meaning humanity in general. Thinking our grandchildren will curse us for not stopping climate change is a luxury of the developed world, for whom further development brings more luxuries, not an escape from poverty. The generations of people born in China and India over the next few decades will not lament the choices that made them some of the world's largest emitters. It will suck to be in a warmer world, but (for them) much better than than the world of the 1970's where they would expect to be born into (and die in) subsistence agriculture and absolute poverty.