The president’s Day 1 actions included directives that fly in the face of legal limits on involving the military in domestic operations and the constitutional guarantee of birthright citizenship.

This is where Mr Trump’s talk of an “invasion” becomes more than rhetorical bombast. Framing the cartels as terrorists invading America is meant to legitimise his use of the law. And because America is being invaded, Mr Trump argues, he can block anyone from crossing the border. The courts may not see it that way. ■

"My office is a law enforcement entity. We are going to follow the Constitution and uphold the law," Krasner said as Trump officials threatened consequences for uncooperative local officials.

In line with Trump’s edict, CNN’s Natasha Bertrand, Priscilla Alvarez, Haley Britzky and Oren Liebermann report. They’re expected to beef up existing operations to support Customs and Border Protection,

President Donald Trump's administration has directed U.S. prosecutors to criminally probe local officials who resist immigration enforcement efforts, intensifying a sweeping crackdown that Trump launched the day he took office.

President Donald Trump's administration has directed U.S. prosecutors to criminally probe state and local officials who resist immigration enforcement efforts, intensifying a sweeping crackdown that Trump launched the day he took office.