I don't think we'd be able to significantly stop the sea rise issue that will face our society in the future. We've done so much damage, the sea level is going to rise regardless. I think we should do what we can to help the problem, but we will face this issue sometime in the near future.
No, we are not too late to stop significant sea level rises, but we must act quickly. If we decide we have waited too long, then we will never do anything to change. We must try to fix the problem now rather than pushing it aside because we think it's too late.
While a good deal of the population chooses to ignore climate change, I feel the issue is gaining many more informed individuals. The evidence of the consequences is becoming to obvious to overlook. I feel enough informed individuals will soon begin to act responsibly to reverse the effects before it is too late.
I don't think we have gotten to the point of no return yet, though I think something drastic needs to happen very soon. We have some amazingly smart people in this world that can certainly find a way to slow, stop, or even reverse climate change, but I do think there is a point where it will be too late. Something needs to happen now.