Trump has taken a far more pragmatic approach to the whole Brexit affair, that is, say less as it's the will of the people. I dont agree with his entire stance but why wade into another nation's internal affairs. Obama, on the other hand, says Britain now moves to the back of the line. What the heck does he mean, Britain has been our best ally before the EU. Trump grasp it and said no, Britain remains in the front of the line. Given it was due process and the people have spoken, it was the best approach. This is a matter for the Brits to decide.
Personally, I think they should have stayed, but those bloody Limeys always have a problem with a dominant Germany!