It doesn't matter if someone said Florida would be underwater by now way back when.
This isn't an exercise of "this guy was right!" or "this guy was wrong!"
This is
(1) acknowledging that the climate is changing, it is because of CO2, and
(2) working with our industries and with other countries to reduce new CO2 emissions and/or capture old ones
(3) planning for eventualities like stronger hurricanes and floods.

I don't think people have much of a problem with 1. It's a freebie.
3 costs money but people understand that tougher infrastructure is a good thing and they can see the results right away.
2 is where all the hemming and hawing is. Lots of people make their living off of fossil fuels and want to convince us that reducing fossil fuel use will make everything cost more and hurt people.

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