Did we cover this somewhere already? If not well, here you have it:
Trump's deputy chief of staff is out: Joe Hagin to leave White House after keeping North Korea summit secrets from Trump to stop him from tweeting – and revelations of links to sex cult (NXIUM)
http://www.dailymail.co.uk/news/article-5862869/Trumps-deputy-chief-staff-Joe-Hagin-leave-White-House.html
This thing is well worth reading in full, lots of details on Hagin and his role in NK negotiations etc.