An executive order said the United States faced a “catastrophic threat” from advanced aerial weapons. But a defense system like Israel’s may not be feasible in the country, which is more than 400 times larger.

President Donald Trump has ordered the development of an "Iron Dome" defense system to shield the United States from an intercontinental missile attack.

Some of the nation’s largest defense contractors are eying roles in President Donald Trump’s plan to build a more comprehensive missile defense system to protect the US.