In American Carnage (p. 511), Tim Alberta quotes Bob Corker on the four things he believes:
I believe that America is a force for good in the world, that the post-World War II institutions have been mostly beneficial to the United States and its citizens...Corker emphasizes that Trump believes none of these tenets of pre-Trump mainstream conservatism.
I believe that free trade has been an outstanding thing for the American people and for our country and for our GDP...
I believe the fiscal issues matter....
And lastly I believe that the domestic institutions that are fundamental to our democracy are important.