How about we take them all, and send TU, OK, A&M, Mizzou and maybe even Arky back to the big 12? Make the 'SE' part of 'SEC' mean something again?
Depends on how you define "southeast."
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The oldest-fashion definition would say "east" is anything east of the Mississippi River, and "south" is anything south of the Mason-Dixon line (the border between Pennyslvania and Maryland, more or less, extended west indefinitely).
By that old definition, Arkansas, Texas, A&M, Oklahoma, and Mizzou would definitely be out. LSU would barely be in, because the campus is on the east side of the river as it runs through Baton Rouge.
But those old definitions give us weird quirks like a school called "Northwestern" ... in Chicago. Because, you know, at the time it was in the northwestern part of the country. Heh.
No, this way of defining "southeast" may be a little too old to still have value.
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Perhaps the best way to determine what's "southeast" is to think culturally. For instance, where is barbeque a real thing? Well, from North Carolina, across Tennessee, and on down to Texas and up to Kansas City. The four most famous truly distinct types of barbeque are "Carolina style," "Memphis style," "Texas brisket," and "Kansas City style." Of course, Alabama and Mississippi and Georgia and the panhandle of Florida, even Kentucky and Virginia fit in this definition nicely.
Not just based on food, of course, there's a whole country lifestyle shared across the south, as far west as Texas and Oklahoma. It's about how we dance, how we talk (anywhere with a twang counts, even if your twang is a little different from mine), how we spend Friday and Saturday nights (year round, not just during football season...but definitely INCLUDING football season), and what values we hold dear.
By that definition, everyone who is in the conference right now fits. And several ACC teams would as well (the Virginia schools, the North and South Carolina ones, Georgia Tech, FSU).
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So I don't mind the idea of Texas and Oklahoma joining in. I wouldn't mind if one day FSU and Va Tech and Clemson and UNC and the North Carolina foursome did.
But by that metric, Miami doesn't fit. Nor Maryland. Nor any of the left coast schools currently scrambling for a home. We should only expand if it makes $$$ sense, of course, but also only if it make cultural sense.
We have a collective identity. We have clung to it just fine, thus far. We should continue to.
Go Vols!