Telling them this will make them vote even stronger in the other way. Especially if you call them stupid, selfish, etc.
You have to show them how it impacts eg. the cost of insurance for coastal properties. But even so, this is hard to convey. The people voting aren't feeling it and are told by coastal elites what to care about - changing their opinion in the opposite direction.
Some countries are even going to benefit tremendously from warming, eg. Russia gets more arable land and access to the North Sea, which is fantastic for trade, energy, and defense.
Sorry, great grand-children.
US and the Western world can continue reducing carbon emissions and it won't make a bit of difference.
Try spending 5 minutes on google before you spout uniformed opinions
Instead of acknowledging the scientific facts and the ethical implications thereof, they engage in "catch me if you can"-tactics.
They let themselves be willfully utilized as a shield of ignorance against the financial restitution they owe. Not to speak of the implied loss of influence in the world economy after fossil fuels are phased out.