Hes trying to have it both ways because what he wants more than anything is a new Cold War with Russia. He is furious with Trump because Trump has said over and over again that he wants to have improved relations with Russia.
McCain just today released his own new defense budget: five years five trillion dollar defense budget; a lot of that is aimed at Russia. It is great for the American military-industrial complex, which is what keeps John McCain in office. So that is one of the reasons he does this. One of the reasons why he cannot stand Donald Trump and he could not stand to have any change in Washingtons anti-Russia policies
Along these lines, McCain has been at odds with Trump over the F-35 program, which involves one of McCain's top donors, Lockheed Martin. A $9 billion deal on the F-35 is near, Reuters reported today.