I doubt NW has any intentions of building a hub at MKE (otherwise they wouldn’t be continuing their downsizing of DTW and using A319/A320 equipment at MKE). I think they’re trying to take advantage of an underserved O/D market, more-or-less creating a “focus city.” It appears to be a well-orchestrated operation… not only does NW stand to gain revenue from an underserved market, they get an opportunity to kill off Midwest Airlines (which appears to be converting into a full-service airline).