That's the thing about Dunning-Krueger. In a narcissist like Trump it makes him literally believe he is the expert in everything. Once he has proclaimed it, regardless of the blatant idiocy of the statement, from that point forward in his mind it's God's own truth, whatever it was he said. Never forget the sharpie that had to be employed to correct the meteorologists about the path of the hurricane. Once he said it he has no way to walk it back. But thank God for that sharpie to show those stupid meteorologists the light of Trump's glory. We won't talk about the fact that the actual path of the hurricane was actually further east than the experts had predicted, making Trump even more wrong.