No mate- no one was talking 'eras' - but rather an established team with an established tradition in town - the plain and simple fact was at that time the town was not able to support the second team that came along later in the same league as the team with the established tradition in the town.
You can't possibly be serious in saying that the Blackhawks are not established with their own tradition in this town and that an expansion team (or whatever dreg that could move here (and the Hawks - iirc would have a say in it) could establish a fan base.
The Cardinals thing was not a hypothetical - but rather an empirical example of a team that couldn't hack it in town under those same pressures -it has nothing at all to do with anything apart from it actually happened that way.
You bring up baseball - ok, let's - but you have to bring up baseball in the sense that say you move the Kansas City Royals into town and expect them to compete with the White Sox ... not going to happen -and really there isn't any reason to.
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Ok, since apparently the example was too tough to grasp - let's try this a different way - the Hawks would have a say in if it ever were to happen - all of the sociological demographics aside- it is a moot point -they have the market all to themselves- and it is written into the NHL bylaws -I don't recall exactly what the radius is - but I remember talk about Milwaukee being a potential expansion city candidate in the 90's and Dollar Bill Wirtz nixing it --- and if Milwaukee was within the radius where the Hawks would have to ok it -naturally Chicago proper would be as well.
So, in all honesty -what exactly is the point? It isn't ever going to happen.