In a Sunday, October 1 op-ed, New York Times opinion columnist David French posits that Christian nationalism may not be "serious," but it is "very dangerous." He argues, "It's not a serious position to argue that this diverse, secularizing country will shed liberal democracy for Catholic or Protest...
Err… that isn’t a strawman. A strawman is where the argument consists of misrepresenting the opposition’s belief or argument in a way that is much easier to attack than the actual argument.
A good explanation with some good examples can be found here: https://www.txst.edu/philosophy/resources/fallacy-definitions/straw-person.html