I grew in in Illinois, in suburban Chicago. I have relatives in Minnesota, Ohio, and Michigan. I am a Midwesterner, and will never be anything else. Acute ears here in Boston can instantly peg me to, not only the greater Midwest, but the Great Lakes area.
So I am surprised that there is debate about which states are actually in the Midwest. In this survey from 538, only 80% of respondents thought Illinois was in the Midwest. Who are these people, and why do they bother having opinions about anything?
To me, the Midwestern states are (West to East): Iowa, Minnesota, Wisconsin, Illinois, Indiana, MIchigan, and Ohio. No Southern states, please. No Missouri, no Kentucky (!), One historical characteristic of Midwest states: they were settled from New England, and they were not slave states. In a sense, you could say that southern Illinois and Indiana are not in the Midwest, by this criterion, being more Southern inflected. It's basically the old Northwest Territory, plus Iowa ("around here, dear, we pronounce that Ohio").
So they have townships, deep glacial soil and a lot of other glacial geography, nice folks who like casseroles (or "hot dishes"), and a scattering of French place names, which they grotesquely mispronounce.
Quick rule: if you could imagine anyone in town volunteering to serve in the Confederate Army, it is not the Midwest. It is somewhere much meaner and more ornery. Maybe more fun, I won't argue about that. But not the Midwest.
And no Great Plains states. Great states, all, but completely different. Less water: not a lot of canoeing. I'd say Midwest is corn and hogs instead of wheat and cattle, but Minnesota and Wisconsin wouldn't fit then. People from Minnesota are incredibly nice, so they want their friends in North and South Dakota to be in the Midwest. I've lived in Massachusetts long enough to say: screw that. Get your own region.
And, seriously, Wyoming, or Pennsylvania? Once words can mean anything, how do you communicate?
Perhaps with a gesture, I guess, which is not visible in this post.