Nevertheless it's nice to be getting JetBlue to fill the gap for Boston and New York rather than just an expansion from American. It's another brand in the MKE arsenal, one with more of a "following" and perception of better product than the AA* RJ's would likely bring. And if opportunities present themselves and Milwaukee responds well to JetBlue there's more likelihood of JetBlue adding something like a FLL, LAS or MCO flight than AA would. Obviously getting ahead of things with a statement like that -- let MKE support the BOS and JFK flights first, of course. But a new airline with a good reputation and product is a bigger win for MKE than if it was simply American added Boston and JFK flights.
B6 or AA adding MKE-LAX nonstop service is also a possibility with
(a) WN no longer serving LAX nonstop from MKE,
(b) LAX no longer having nonstop service from MKE on a non-ULCC (even though NK has recently added MKE-LAX nonstop service),
(c) B6 recently adding nonstop service to LAX from a few other B6 destinations (in addition to the routes that B6 had moved over to LAX from LGB),
(d) AA currently being the only airline serving CLT, DFW, and PHL nonstop from MKE (even though WN currently has plans to resume MKE-DAL nonstop service), and
(e) WN being weaker in the MKE market than it was prior to the COVID-19 pandemic with the loss of WN MKE-BOS/CLE/LAX/LGA nonstop service and the suspension of WN MKE-DAL nonstop service during the pandemic.
AA adding MKE-DCA nonstop service is a possibility with
(a) the lack of competition that is there on the MKE-WAS route with WN currently the only airline serving the WAS market nonstop from MKE, with WN serving DCA and BWI nonstop from MKE,
(b) AA currently serving DCA nonstop from ORD, CVG, CLE, CMH, DAY, DSM, DTW, GRR, IND, MCI, LAN, MSP, and STL in the Midwest,
(c) MKE-WAS being one of the top routes within the contiguous U.S. that doesn't have nonstop competition, and
(d) the connections that AA would be offering to other East Coast destinations through DCA.
UA adding MKE-IAD nonstop service is a possibility for similar reasons, even though IAD isn't slot restricted, there is connectivity onto Star Alliance transatlantic flights at IAD, and UA offers connections at IAD to some smaller Eastern U.S. markets that don't have any nonstop service from DCA or BWI.
There are also some adds that could be made by AS out of MKE to strengthen AA/B6/AS's position in the MKE market such as the return of AS MKE-PDX nonstop service or the addition of MKE-LAX/SFO nonstop service.