I think Mitch and Paul were begging Trump not to throw them in the briar patch.
They've been tossing him in the briar patch for months.
The truth is that too many GOP members of Congress value publicly separating themselves from Trump with snarky asides and leaks than actually passing legislation. As a result, Congress has passed almost nothing of value. Obamacare is intact, no tax reform, no wall. I would not be the least bit surprised to learn that they are laughing behind their backs at Trump regarding financing for the wall.
So, Trump basically just flipped them the bird and called them out as ineffective. The message sent was "if you.don't have my back, I don't have yours."
Maybe that will wake them up and restore their spines, though I doubt it. If it doesn't, the midterms will be massacre because a whole lot of GOP voters are going to sit home.