Does it make a decent domestic political payoff, does it overturn the Obama administration, move international law, and annoy the European Union? If so, it is probably a foreign policy decision by the Trump administration.
Perhaps more importantly for the President of the United States, Monday's ruling was a gift to conservative evangelical voters who support Israel for reasons of biblical prophecy, as well as to its donors in the United States, who also support right-wing politicians in Israel. The administration says the change could bring about just peace in the Middle East, and that it took a year of legal analysis to reach that decision.
The political attitudes of every president naturally influence American foreign policy. But no recent administration has been so keen on Trump to destroy lasting positions in US policy – even at the risk of violating American values.