BELIEFS
Without any scientific evidence, then candidate, Donald Trump declared climate change a hoax. He convinced nearly all of his supporters as such, and materialized a substantial platform from nothing. Ultimately, his platform was based on populism and placing America first, claiming that the Paris Agreement unfairly harmed American jobs and industry, tapping into the same feelings that won him presidency.
THE US IS THE ONLY DEVELOPED COUNTRY WHO PLANS ON NOT JOINING
Every country in the world except Syria and Nicaragua pledged to sign and ratify the Paris Climate Agreement before Trump. Now the US is the only developed country that is not part of the agreement.
PARTY EFFECTS BELIEF
Though a majority of every party supports reducing carbon emission, Republicans are significantly less concerned with the effects of climate change.
EVEN TRUMP SUPPORTERS BELIEVE IN THE PARIS CLIMATE ACCORD
Regardless that there favored candidate doesn't believe in climate change, a plurality of his supporters view the withdraw from the Paris Agreement negatively. This indicates that a platform without scientific evidence can only go so far.