> It is a risk that ruling by executive decree entails.
The problem is the gross disconnect between Local, State, and Federal interests. Polls have support for the Paris agreement well into the majority, beyond the margin for error; were it to head to something like a referendum, the US would have signed onto the Paris agreement.
And even that being the case, President Obama was well aware of the fact that it never would have been ratified by the Senate.
The international credibility problem also reaches critical levels when you consider that the United States has 4 year terms but signs onto 20 year agreements, when the political sphere is so radically split. Every four years, the International community is forced to hold its breath as one of the top world superpowers seemingly flips a coin as to whether or not it will uphold its bargains. It is worth noting that this wasn't always the case; it was standing tradition that you followed through on a previous administration's agreements, simply to maintain credibility.
Whether it is a function of Trump himself, his die-hard base, or a large group of confluent factors (my vote is for this one), this tradition of maintaining credibility despite political cost holds very little water with the current administration. Worse, this is exactly what his base seems to want and clamor for. They are painting a political climate where the country takes a 180 degree turn (rather than, say, a 120 degree curve) every 4 to 8 years.
How long can a country in a global economy at the scale of the United States maintain that strain without snapping? It'll be interesting to watch, if nothing else.