I would point out at least two present issues with your list vis-a-vis what a 21st century conservative should be. 1. Communism is pretty much dead, and this tenant provides little guidance. 2. “American exceptionalism” sounds an awful lot like “manifest destiny” and an invitation to American hegemony. Moreover, it sounds trite and hypocritcal when used by a country that hasn’t walked the walk since RR left office.
Communism can easily be replaced with Islamic terrorism.
To me, American exceptionalism means that we adhere to our founding principles and do not sacrifice them to go along or get along with other countries. I do believe that the U.S. is the greatest nation on earth - although we’re not perfect by a long shot. Just a lot better than all the others.
I don’t believe it has anything to do with manifest destiny and I don’t think Reagan believed that, either.
Maybe the wording, American exceptionalism, is dated and open to interpretation, but I understand what Reagan meant by it. He was extraordinarily proud of the U.S., was humbled by those who trusted him to lead us, and showed sincere reverence toward the office of the President.
A real world conservatism must also advise how to fight the battles here at home.