Washington (CNN) There's a strain of thinking in some Washington political circles that goes like this: Donald Trump isn't going to get re-elected and may not even last out his entire first term. Given that, he's rightly seen as a bump in a much longer road -- and one that will be forgotten soon after he leaves office.

That logic is flawed. And Trump's decision to pull the US out of the Paris climate accord , which has not yet been announced but is being widely reported, shows why.

Simply put: Decisions he makes -- every day -- change the course of the country on everything from climate to immigration to trade. The idea that all of this can be undone the second Trump leaves office -- whether in four or eight years -- is a massive misjudgment of not only how difficult it is to turn the ship of state but also of the ways in which the world perceives the U.S. will have changed in that time.

Let's go back to the beginning on the Paris deal.

Trump railed against the climate deal -- agreed to by then President Obama in 2015 -- during the 2016 campaign and held it up as a prime example of how the US makes bad deals.

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