1. Divisions deepened over President Trump’s order barring entry to refugees and citizens from seven Muslim-majority countries.

Some of Mr. Trump’s supporters applauded the order, but other citizens organized on social networks, business leaders registered objections, and State Department diplomats circulated a so-called dissent cable. The White House press secretary said government workers should “get with the program” or go.

Donations poured into the A.C.L.U. and other rights groups, lawsuits proliferated and acting Attorney General Sally Yates, a holdover from the Obama administration, was fired after she ordered the Justice Department not to defend the order in court.