To the editor: Regarding Roger Cohen's op-ed, "Trump's Iran Derangement" and his assertion that refusing to certify the Iran deal "would send a strong signal that the United States has become a bait-and-switch power whose word is worthless," Mr. Cohen seems to forget that it wasn't the United States which gave its word, but President Obama. Although the deal should have been dealt with as a treaty and submitted to the Senate for approval, Obama dared not because a solid majority of both Congress and the people wisely opposed it. President Obama himself set a precedent of reneging on commitments of predecessors, making it clear that a presidential promise couldn't be counted on to last beyond his administration. And let's not forget that Iran, besides blatantly violating the spirit of the JCPOA, has also been acknowledged to have violated the terms of the agreement at least twice by exceeding the amount of heavy water allowed. We even rewarded Iran for one of those violations by buying the excess ourselves! Sincerely, Alan Stein