Homeland Security Secretary Kirstjen Nielsen resigns, what’s next for immigration policy?

More top officials at the Department of Homeland Security will reportedly be out just one day after Secretary Kirstjen Nielsen resigned. Nielsen became the public face of the administration’s child separation policy last year, even though she was reported to be more ambivalent about it than other administration officials. After announcing Nielsen’s resignation Sunday, President Trump tweeted “our country is FULL!” The president also tweeted that the commissioner of U.S. Customs and Border Protection Kevin McAleenan will be stepping in as acting secretary. But that announcement raises some legal questions.