Shapiro served as Deputy Assistant Secretary of Defense for the Middle East until January—charged with, among other things, considering scenarios in which tensions between Israel and Iran escalated into all-out war and preparing U.

The United States is the main international backer of Israel, Iran's biggest regional foe. It is also a close ally of Sunni Gulf monarchies which for years pursued their own rivalry with the Islamic Republic, seeing it as their main regional threat.

Trump told the Wall Street Journal that he knew all about Israel’s plan ahead of time, that he wasn’t given a mere “heads-up.”

The country’s exports mostly come from Kharg Island in the Persian Gulf. But Israel’s energy facilities are also at risk.

The United States has pulled some diplomatic staff and military families out of the Middle East, citing unspecified regional security risks.

Iranian officials said on Friday that the United States "shall be held fully accountable" for its support of Israel after the nation took out key Iranian nuclear facilities and killed government leaders in a series of air strikes this week.

Israel’s leader and President Trump appeared to bet they can persevere, but other world leaders warned of unintended outcomes in a volatile region.

National security experts warn that Israel's attack on Iran shows why Chinese land and asset purchases in the U.S. pose a significant threat to American security.