Iran has been stepping up the threats.
Via ABC:
The U.S. military is deploying a Patriot anti-missile battery to the Middle East to further deter threats from Iran, the Pentagon announced on Friday.
The Pentagon would not specify the location but a senior military official said it would arrive “relatively soon.”
The decision follows an announcement earlier in the week that the U.S. would deploy a carrier strike group and bomber task force to the region in response to indications that Iran and its proxies were preparing to attack U.S. forces and interests in the region.