I think we are somewhat talking past each other.
An American traditionalism could have worked, but conservatives aren't traditionalists. What happened in both the USA and the UK is that the reaction against liberalism coalesced ideologically and organizationally around the principle of being completely against action. Liberals act, conservatives slam on the brakes. When you're ideologically against action, you're also against seeking and using power. Conservatism, referring here to that Burke-descended ideology that has had the American right by the throat for over a century, has no intrinsic principle motivating its adherents to try and obtain power. Power is a means, and conservatism has no ends. Thus conservatives found themselves incrementally expelled from every institution.
In politics, whoever has the initiative has an advantage. If I have an agenda, and your only agenda is to stop me, then the natural outcome is for me to get at least part of what I want. The Trump administration is a good example of this. The entire force of American government was arrayed against him, but their only agenda was to stop him. He was able to get part of what he wanted on the border, trade, and war because the only agenda anyone else had was "not that!"
What we see is that when you have a vision and a goal, something motivating you to get power and use it, you can get somewhere.