He thinks he can, but he can’t. Orange Julius Caesar will say whatever Marcon most wants to hear at the moment, then just change his tune and pander to his base after the visit ends. Marcon will end up looking like the fool he was for thinking otherwise.
After all, even members of Trump’s own cabinet have trouble working with him, because Trump’s line on what he wants keeps continually changing. Trump’s own well-demonstrated personal flaws make cutting any sort of lasting deal highly improbable.
It’s somewhat surprising a reasonably intelligent person like Marcon could think his effort will end up otherwise. I guess in some sense he has to make a good faith effort to try and save the doomed Iran deal; it would look really bad for him to just write Trump off from the get-go. It’s one of those pointless formalities that must be gone through.
On a different matter, so much for the idea that Rand Paul might act as something other than Trump’s dutiful lapdog. The lapdog might yap a lot and even let out the occasional growl, but it’s always the smallest and most pathetic dogs that are the most vocal.