The prince and the captain squared off this week and in the end, the prince — not accustomed to losing — never had a chance.

And for that, veterans around the city are applauding the captain, also known as US Representative Seth Moulton, a highly decorated veteran and former US Marine captain who served four tours of duty in Iraq.

The prince is our secretary of state, William Francis Galvin, who for a generation has been known around Massachusetts politics as the “prince of darkness’’ for his dour-faced and wily political skills that usually help him get what he wants. Not this time.

Here’s what happened:

Brighton Marine Health Center sits on a small hill near St. Elizabeth’s Medical Center. The health center there had a plan that had virtually every stakeholder who reviewed it nodding in enthusiastic agreement. Not Bill Galvin, a Brighton resident, who fashions himself as the unofficial mayor of his neighborhood.

Working with developer WinnCompanies, the health center is seeking public funds to help develop 108 units of housing. Most of those units would be below market rate. All of them are intended for veterans.

Here’s the rub: To accomplish that, Brighton Marine, which serves veterans and their families, wants to demolish three squat, red-brick buildings on its campus along Commonwealth Avenue. The so-called historic buildings, which date to the late 1930s, have been empty for 20 years. In their place, a six-story $40 million housing complex would be built next to two more old buildings that would be preserved and used for programming space.

I have toured the buildings targeted for demolition. If they’re historic, I’m the queen of England. But Galvin oversees the Massachusetts Historical Commission, so he’s got leverage here.

Moulton told me this week that he agrees with me. “[Galvin] obviously feels they are historic buildings, but I guess I share your perspective on it,’’ the first-term Democratic congressman told me. “It’s hard for me to understand how they’re historic from looking at them.’’

So Moulton and Galvin had a little talk. “He was trying to explain something about how he was concerned about the frontage on Commonwealth Avenue,’’ Moulton said. “I didn’t understand that. To me, there’s nothing wrong with having veterans housing on Comm. Ave. To me, that didn’t seem like a major concern.’’

Major concern? Where Galvin sees a petty, small-time turf war, Moulton, whose district is on the North Shore, not in Boston, sees something that is the opposite of petty. He sees a chance to help veterans who have placed their lives on the line for us. “They deserve the best,’’ Moulton told me.

And he told the same thing to Galvin this week in a blunt letter that immediately dislodged the Galvin-constructed roadblock that had threatened to derail or destroy the project.

Allow me to paraphrase Moulton’s message to Galvin: Knock off the nonsense. Get back to the negotiating table. Resolve remaining issues.

“Many veterans who return back home after their service to our country have trouble finding affordable, quality housing in Boston,’’ Moulton wrote to Galvin. “Some of these service members grew up in the city, and cannot afford to come home. Others have found employment in important civil service roles, but struggle to find housing that meets the city’s residency requirement.’’

Then, for good measure, he added: “These young men and women have served our country and now they seek to be actively engaged members of the community. I believe that we owe it to them to find a timely solution.’’

Game. Set. Match.

A day after Moulton’s letter, the long-stalled negotiations resumed. The rhetoric has softened. Mayor Martin J. Walsh’s administration supports the project and is applauding renewed negotiations that it expects will bear fruit.

“The advocacy and stature of Congressman Moulton did move the needle,’’ said Michael Dwyer, chief executive officer of Brighton Marine Health Center, who had been perplexed — and visibly angry — at Galvin’s intransigence. “We took the high road. The street fight’s over. I won’t say we’re in the end zone, but we’re at the 50-yard line. In the next 30 days, we have to come together as a group.’’

You can bet that will happen. And it will happen because Moulton did something deceptively simple. He reached across district lines. He saw a need for a constituency as valuable to him as to Sixth Congressional District voters: those veterans the politicians are always telling us they value so dearly.

Galvin wouldn’t talk to me about any of this.

The actions of Moulton, twice decorated for heroism, speak vastly louder than any words.

Thomas Farragher is a Globe columnist. He can be reached at thomas.farragher@globe.com.