The level of cooperation demonstrated by the Mashantucket Pequot and Mohegan tribes in their effort to build a so-called satellite casino in north central Connecticut shows how concerned are the tribes about the increased competition facing their respective Foxwoods Resort Casino and Mohegan Sun Casino operations.

These two tribes have long competed against each other to draw casino patrons to their respective gaming and entertainment empires. They also have some historical enmity.

But there were Rodney Butler, chairman of the Mashantucket Pequot Tribal Council, and Kevin Brown, chairman of the Mohegan council, shaking hands and smiling after making their new alliance formal at a signing ceremony at the State Capitol on Thursday.

The two tribes intend to build their jointly held casino on the Interstate 91 corridor north of Hartford and south of Springfield, Mass. The expectation is that casino patrons from the Greater Hartford area who might travel to a new MGM casino planned in Springfield will instead visit the closer Connecticut venue, keeping jobs and revenues in the state.

It is a plan that this newspaper has endorsed, while recognizing it still faces significant hurdles that could block it. And at best it will minimize the impact of increased casino competition from Massachusetts and other states. Jobs will still be lost as casinos open elsewhere.

A bill approved in the last session gives the two tribes the chance to present a specific proposal and location that the General Assembly could act on in 2016.

Not surprisingly, MGM has launched a legal challenge, questioning in federal court the state’s authority to give the two tribes exclusive rights to build and operate a casino on non-tribal lands, without opening the process to competition. The challenge raises legitimate legal and policy questions.

Political support for the proposal is not that strong in Hartford, one reason the legislation passed this year was hardly definitive. Critics of the plan argue that casino operations have reached a saturation point in the Northeast, so Connecticut should not allow another.

We, however, urge Gov. Dannel P. Malloy to continue working with the tribes on the satellite casino concept, while mindful the legal and political obstacles could prove too great.