At age eighty-three, Donald Rumsfeld has overseen the launch of a mobile game, Churchill Solitaire. STILL FROM https://youtu.be/ySnY9HBUAxI

On a drizzly winter afternoon, Donald Rumsfeld arrived at a fourth-floor steakhouse overlooking Columbus Circle, tossed his overcoat into a booth, and ordered a cup of coffee. His silver hair was brushed back in a bicorne shape; his small, twinkling eyes suggested that he was savoring a private joke. At age eighty-three, he had overseen the launch of a mobile game, Churchill Solitaire, and come to New York for a ­slog of promotional interviews—the “Today” show, “Fox and Friends,” Sean Hannity, Stephen Colbert, “Morning Joe,” and “The View,” plus some radio, with Jake Tapper and Charlie Rose still to come. Nevertheless, he was cheerful. “This is all fun!” he said, brightly, when asked if he’d had time for fun. “Meeting you is fun! My goodness!”

Rumsfeld came to New York late Sunday, by train. By Monday, his media offensive was spreading across Twitter, prompting me to e-mail his Churchill Solitaire colleagues around lunch. I received final word at midday on Tuesday: Rumsfeld would meet me, two and a half hours hence, for a fifteen-minute steakhouse coffee. After that, I could accompany him to the CNN green room and watch as he taught his game to a millennial producer.

Sitting with us at the steakhouse was Keith Urbahn, Rumsfeld’s co-developer and protégé. He spoke about the app’s hundred-thousand-plus downloads with the shy pride of a new father. Urbahn first met Rumsfeld as a Pentagon speechwriter, and was later chief of staff in Rumsfeld’s private office, where he achieved minor fame by being the first to tweet early reports of Osama bin Laden’s death. Along with another former Washington speechwriter, Urbahn helped write Rumsfeld’s memoir “Known and Unknown,” and co-founded a literary agency named Javelin, the Secret Service code name of Rumsfeld’s wife. The agency brought Rumsfeld’s second book, “Rumsfeld’s Rules,” to market, and negotiated a $1.5 million advance for “A Time for Truth,” by Senator Ted Cruz.

“I took a young hunk of clay out of Yale and have been trying to improve it over these decades,” Rumsfeld cackled.

“It was a painful process at times,” Urbahn said. “He operates out of his inbox.”

“My outbox,” Rumsfeld corrected.

“Did I say inbox? Outbox.”

“Your_ _inbox!” More cackling. He had brought his arsenal of humor: the smirk was like a boxer’s jab; the cackle locked in gains; the low chuckle nodded to the ironies of the cosmos.

“I’m constantly getting snowflakes,” Urbahn said, referring to the famously deep drifts of Rumsfeld memos, recorded by Dictaphone and fired off to Urbahn’s team of programmers. Urbahn learned of Churchill Solitaire as part of his education, on a flight with Rumsfeld to Taos, New Mexico. Rumsfeld dealt out two decks of miniature playing cards, “from somewhere in Europe,” Urbahn remembered. “Switzerland,” Rumsfeld specified. To illustrate, Rumsfeld’s spokesperson, Remley Johnson, produced two similar decks from her satchel. The game is much like regular solitaire—founding aces, flying kings—tweaked by the addition of six cards that must proceed directly to the foundation without passing through the tableau. They are known as the Devil’s Six.

Rumsfeld told Urbahn that he’d learned the game from the late André de Staercke, a Belgian diplomat, and that de Staercke had said he’d learned it from Churchill himself. Years later, Javelin got the imprimatur of Churchill Heritage Ltd., which told the Wall Street Journal that the game’s provenance is “entirely credible.” Churchill was an avid chronicler of his own life, and while the record contains ample evidence of him relaxing with painting, drinking, gambling, and a French card game called bézique, there are no mentions in his papers or letters of this special form of solitaire. All the same, “the absence of evidence is not evidence of absence,” as Rumsfeld himself pointed out, in June, 2002.

In his interviews, Rumsfeld played the elder statesman, batting around questions on new threats, old wars, and the G.O.P. primary. He palled around with the ladies of “The View” and twisted his fingers as Colbert gave him a thorough grilling, quoting from a 2002 memo from the Joint Chiefs of Staff, which warned that the case for Saddam Hussein’s weapons program was based on “imprecise intelligence.”

“Government’s not perfect,” Rumsfeld replied. “Look how long it takes to get snow removed.”

Hannity was more friendly. “Go back to Vietnam,” he said. “We could have won Vietnam.”

“Mmm-hmm,” Rumsfeld hummed.

“But it became politicized,” Hannity said. “Iraq became politicized.”

I asked Rumsfeld whether Churchill Solitaire might communicate something about war to an audience that might not have Rumsfeld’s “firsthand knowledge and experience.” This was a slightly trollish question, as Churchill’s time in the trenches of the First World War is a different universe from Rumsfeld’s (just as Rumsfeld’s years as a Navy pilot are a different universe from mine).

“I wouldn’t say that,” Rumsfeld replied. “I wouldn’t say that it links to war. I’d say it links to Winston Churchill as a person.”

I did not bring up the newspaper headlines reading “WAR! WAR! WAR!,” which open the online trailer for Churchill Solitaire, followed by the Prime Minister’s desk blotter, deep in the bunker where the British war cabinet took refuge from the Nazi blitz, which provides the app’s martial ambiance. A bomb hits; the room shakes; the cards scatter. “Churchill Solitaire will keep you coming back,” a wizened, Churchill-like voice intones, “battle after battle, deal after deal, until victory is won.”

Creating an app, Rumsfeld said, “is like any other set of problems. You decide what you want to do, and you set a goal, and you get good people who can do it, and then you work it and work it and work it, and refine it and fix it and change it and alter it, and make it better. It’s just hard work, that’s all.” He seemed to be repeating the core dogma of our civilization, from General Motors to the Pentagon to the App Store: the world consists of problems. Every problem has its fix. There is no such thing as a problem that would be better off left alone.

The basic version of Churchill Solitaire is free. For $5.99, players can purchase a hundred “hints” or “undos.” On the way from coffee to the Jake Tapper spot, Rumsfeld reflected on the paid features. “The hints are true in life,” he said, as the elevator descended. “You can always call someone who has more experience than you do, and get some thoughts from them. But there are very few undos in life.” He chuckled to himself. “I mean, the way things work? There are very few take-backs.”