Vaughn Hillyard, NBC News Correspondent joins Nicolle Wallace on Deadline White House to discuss Nikki Haley’s endorsement of her former Presidential primary opponent Donald Trump who she has said is dangerous, has cognitive decline, all to keep in good standing in the Republican party, which has become the party of Trump.  » Subscribe to MSNBC: youtube.com/msnbc Download our new MSNBC app for the latest breaking news and daily headlines at a glance: msnbc.com/information/download-msnbc-app-n1241692 Follow MSNBC Show Blogs MaddowBlog: msnbc.com/maddowblog ReidOut Blog: msnbc.com/reidoutblog MSNBC delivers breaking news, in-depth analysis of politics headlines, as well as commentary and informed perspectives. Find video clips and segments from The Rachel Maddow Show, Morning Joe, The Beat with Ari Melber, Deadline: White House, The ReidOut, All In, Last Word, 11th Hour, and Alex Wagner who brings her breadth of reporting experience t...