It is, but not on its own. Only when compared to the larger canon of conservative thought in which these principles are only applied to things they have preference against.
If a conservative doesn't like it and the federal government is protecting it it's a states rights issue. If a conservative does like it and the federal government isn't protecting it it's a constitutional issue.
There is no well reasoned principal backing these beliefs. It's merely a facade of justification put on top of preferences.