Maybe it is to give Kevin McAleenan enough rope to hang himself and Obama from a new angle?
Isn't Kevin McAleenan just a temporary fill-in, with the permanent secretary to be named later to go through Senate confirmations? He probably will not be there long.
I am waiting to see what happens before passing judgement. I think this will be like most of Trump's moves: they look HORRIBLE at first, and then the surprising twist happens, and it turns out better than expected.