Latest on U.S. military buildup in the Middle East; Saudi Arabia nuclear deal

Sources say the United States military is building up its forces in the Middle East as President Trump warns that it will hold Iran accountable for any Houthi attacks. Meanwhile, Saudi Arabia has yet to respond after President Trump said the Saudis would have to join the Abraham Accords in order to finalize the U.S.-Saudi nuclear deal. CBS News' Kathryn Watson breaks it all down.