Here's a quick thought that is bound to be controversial in some circles:
Christian Nationalism is a problem in the United States.Now here is a slightly longer and more nuanced thought that is almost certain to be even more controversial in some circles today:
Placing the word "white" in front of "Christian nationalism" in the statement above does not make the statement any more (or less) true, powerful, or persuasive.
I fear that we are making a mistake to focus on "White Christian nationalism" instead of "Christian nationalism." It refers to a somewhat smaller group, incorporates race unnecessarily, and obscures the uncomfortable reality that not all Christian nationalists are white people (although most do appear to be). I know we don't want to admit that a person of color could be a Christian nationalist, but our reluctance to do so does not make it any less true. Moreover, I submit that Christian nationalism, Christian extremism, Christian dominionism, or whatever term you prefer for these overlapping phenomena are all problematic regardless of the race or ethnicity of those involved. That is, what makes them concerning isn't race but ideology.
While I would agree that the combination of white supremacy and Christian nationalism may be worse than either one on its own, I'd hate to see us ignore Christian nationaism, Christian extremism, and so on unless it includes white supremacy. Doing so almost certainly means more Christian privilege. That's something I don't think any of us wants.
To be clear, white supremacy is a significant problem regardless of whether it involves religious trappings. Similarly, Christian nationalism is a significant problem regardless of whether it involves white supremacy. Both can and should be opposed, but I fear that attempting to merge them so that we do not talk about one without the other may make it harder to oppose either. Once again, I don't think that is something any of us wants.