Just a few years earlier, Obama had withdrawn U.S. forces from Iraq, in effect delivering America’s Iraqi allies to Iran on a silver platter. Iran would now have a land bridge all the way across Iraq, Syria, and Lebanon to the Israeli border, and could hardly be expected not to take advantage it. Moreover, while it was no doubt true that dealing with Iran would be less difficult if it didn’t have the bomb, the nuclear deal didn’t exactly solve that problem, because it left Iran with all the basic elements of both a plutonium- and uranium-pathway serial production capability for nuclear warheads, which it could activate in a matter of months. Third, the deal itself was seen by many in Tehran as a surrender on America’s part, not entirely without justice considering the U.S. had caved on the key demands in U.N. Security Council resolutions going back nearly a decade. For all these reasons, Obama’s well-wishes notwithstanding, the baseline presumption had to be that Iran would feel emboldened, and it would it would be more, not less, difficult to deal with Iran’s other “nefarious activities.”

And so it proved. In Iraq, Iranian support for Shiite militias translated into influence over the Iraqi government itself. In Syria, Obama acquiesced to Russia’s and Iran’s entry into the civil war, making Assad’s eventual victory a foregone conclusion. In Lebanon, Hezbollah has all but completed its takeover of the state. The rise of ISIS brought the U.S. back to Iraq after a brief interregnum, but under a dispensation which left Iran free to continue its subjugation of Iraq. As such, the U.S. arguably served as Iran’s proxy air force in Iran’s fight against ISIS, further helping to cement Iran’s regional hegemony.

Though it was surely not his intention, Obama’s strategy in many ways boiled down to appeasement. When President Trump came to office, Republicans saw an opportunity to undo the hated deal. They put relentless pressure on the president to withdraw from it, which he eventually did. Secretary of State Mike Pompeo announced a return to withering sanctions, tied to maximalist demands that exceeded even those of the Bush administration.