U.S. military expands presence in Persian Gulf as Iran faces more sanctions

The U.S. military buildup in the Persian Gulf continues, as the U.S. deploys submersible sea drones to help clear mines laid by the Iranian navy. These are in addition to the two U.S. aircraft carriers, multitude of mine-sweeping ships, and the USS Ponce, which can be a forward staging base for operations, that already patrol the Gulf.

The U.S. hopes an increased presence will deter the Iranians from closing the Straight of Hormuz – through which about 20% of the world's oil exports travel – in response to tightening international sanctions. But could the combination actually work to provoke the Iranian government into lashing out?

CNN Contributor and former Homeland Security Adviser to George W. Bush Fran Townsend has more on these developments.