California Gov. Gavin Newsom said in a Monday post that California will sue President Trump, saying he "illegally acted" to federalize the National Guard during protests against federal immigration enforcement in Los Angeles The big picture: Trump on Saturday signed a memorandum calling in the National Guard — despite opposition from the state's and the city's Democratic leadership.

The situation has all the elements that the president seeks: a showdown with a top political rival in a deep blue state over an issue core to his agenda.

Gavin Newsom asked the Trump administration on Sunday to rescind its move to deploy 2,000 California National Guardsmen to Los Angeles to subdue immigration protests, accusing the White House of illegally overriding his authority and intentionally inflaming tensions with protesters.