It's time for the United States to hold Iran accountable.

President-elect Donald Trump’s nomination of retired Marine Gen. James Mattis as secretary of defense likely spells trouble for the U.S.-Iran nuclear deal.

Mattis was reportedly forced to retire five months early as commander of U.S. Central Command in 2013 by the Obama administration for being too hawkish on Iran. Mattis did not oppose the deal itself, but instead asked provocative questions about the long-term impact of the deal.

Questions he posed to President Barack Obama and his team included, “what do you do with Iran once the nuclear issue is resolved and it remains a foe? What do you do if Iran then develops conventional capabilities that could make it hazardous for U.S. Navy ships to operate in the Persian Gulf?” When officials would answer or demur he would say, “And then what?”

Iran is “the single most enduring threat to stability and peace in the Middle East,” Mattis said in April 2016, echoing the concerns that got him forced out of the administration. The Iran nuclear deal is also signed by Russia, Britain, France, China and Germany.

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