Imagine for a moment that you go to a doctor because you have an upset stomach. The doctor runs some tests and finds that you have a stomach tumor. Thankfully, he said he will treat the tumor before it kills you. As you prepare for surgery, the doctor tells you, "There is no tumor."
You know there is a problem. You have seen the images. Your stomach gets progressively worse. Your body is degenerating. You ask the doctor why he will not treat the tumor. His response is that obviously previous doctors lied to you, despite the fact that previous doctors intentionally avoided the subject altogether. Furthermore, the doctor tells you to be grateful that your stomach still digests tasty food: "Shut up, patient. This is all in your head. Enjoy your cheeseburgers." You are dying, you know you are dying, the doctor who identified the problem told you that you were dying, and then, that same doctor just walked away.
In effect, that is what Trump just did to the 78 Million Americans who voted for him.
He told them there was a problem. Trump was right. He promised to fix the problem. Trump was right to do so. He pointed out the existing evidence. Trump was right, again. Yet, at the critical moment necessary to finally address the issue, Trump walked away from the crisis and blamed his supporters who are rightfully disappointed.