“What’s the Matter With Kansas Iowa?”**
In modern English, a shibboleth can have a sociological meaning, referring to any in-group word or phrase that can distinguish members from outsiders – even when not used by a hostile other group. It is also sometimes used in a broader sense to mean jargon, the proper use of which identifies speakers as members of a particular group or subculture.
–Wikipedia
Once upon a time, if you were a Twin Cities Realtor trying to drum up business around the City Lakes, you had to be careful to call it “Lake Calhoun,” not “Calhoun Lake” (the lake was renamed “Bde Maka Ska” in 2018). See, “Calhoun Lake??” Is that by Isles Lake?.”
Similarly, if you’re a national correspondent for The New York Times doing a deep dive on Iowa politics, post-Trump(?), you’d better refer to the region as the locals do.
That is, “Upper Midwest,” not “northern Midwest.”
Shibboleths Then & Now
Unlike in biblical times, tripping over a shibboleth today won’t get you killed by an enemy tribe.
But, it will mark you as an outsider, and undermine the credibility of anything else you say — or write . . .
See, “Why Iowa Has Become Such a Heartbreaker for Democrats,” Trip Gabriel; The New York Times (4/27/2021).
**The title of a 2004 book by Thomas Frank.