Delta is attempting to defend its turf in New York, as it adds two new routes that go head-to-head against JetBlue Airways.The Atlanta-based carrier filed new service over the weekend for flights from its New York-JFK hub to Kansas City (MCI) and Milwaukee (MKE), according to Cirium schedules and later confirmed by a carrier spokesperson. Delta will fly the routes daily beginning on June 6, 2022, and they’ll be operated by regional affiliate Endeavor Air.Want more airline-specific news? Sign up for TPG’s free new biweekly Aviation newsletter.The carrier will deploy a 76-seat CRJ-900 on the Kansas City flight, and a 69-seat CRJ-700 on the Milwaukee service. Delta last flew these routes back in 2013, and they haven’t been operated since then.(Map courtesy of Cirium)While two new domestic routes to cities in the Midwest may not usually grab headlines, it’s the competitive undercurrent that’s most interesting here. In fact, these two markets also happen to be JetBlue’s newest cities from JFK and Boston. The New York-based carrier inaugurated service to both cities just a few days ago (on March 27) after first announcing them in April 2021.In July 2020, JetBlue teamed up with American Airlines to launch a so-called Northeast Alliance, where the two carriers would combine efforts in the New York and Boston markets to grow their networks, boost frequencies and offer reciprocal loyalty perks.That partnership has since become a major thorn in Delta’s side as the airline tries to compete with JetBlue (and American) for supremacy in the highly competitive Northeast market.To date, we’ve seen Delta respond to the competitive pressure by adding routes and bringing its most modern planes, including its new domestic workhorse, the Airbus A321neo, to its Northeast hubs.When American Airlines and JetBlue unveiled their Northeast Alliance, the two airlines promised plenty of growth in New York and Boston.Sign up for our daily newsletterEmail addressSign upI would like to subscribe to The Points Guy newsletters and special email promotions. The Points Guy will not share or sell your email. See privacy policy.The two carriers have since launched a slew of new routes, and American also started two new high-profile destinations from New York-JFK: Athens and Tel Aviv. Delta moved nearly a year later by adding its own service to both Athens and Tel Aviv from Boston.Delta’s competitive response comes as the Northeast Alliance has faced increased scrutiny from regulators, culminating in an anti-trust lawsuit filed by the Department of Justice in September 2021. In the suit, the DOJ argues that the pact allows for anti-competitive coordination between the two carriers.For its part, Delta confirmed the network adjustment with its boilerplate statement. “We continue to monitor and adjust our flight schedules and route network based on customer demand," a carrier spokesperson shared with TPG.Along with the two new flights, Delta is cutting four routes from its Minneapolis-St. Paul (MSP) hub, as follows:DestinationEffective dateAlbany (ALB)Sept. 6Providence (PVD)Sept. 5Rochester (ROC)Sept. 6Syracuse (SYR)Sept. 12The cuts in the Twin Cities primarily affect connectivity to upstate New York and New England. Delta will continue serving all four cities from its New York hubs, as well as with flights from Atlanta and Detroit.(Map courtesy of Cirium)Meanwhile, from JFK, Delta is pulling out of the Houston (IAH) market, which was scheduled to resume from its pandemic-related suspension on Sept. 12, 2022, a move that’s likely due to the slower-than-expected recovery in business travel demand.