Wikipedia is a lot better now, but any site that has hundreds of thousands of words of discussion over which dash to use and when is obviously toxic.
Here is an n-dash, an m-dash, and a hyphen. –,—,-
We expect discussions about wars to be tricky, but we don't expect discussion about the punctuation used in titles to be so hard: Read the "Mexican–American War" / "Mexican—American War" discussion here: https://en.wikipedia.org/wiki/Talk:Mexican%E2%80%93American_...