HALIFAX, Nova Scotia—It's amazing what some fresh Nova Scotia air can do.

Sens. John McCain and Tim Kaine led a congressional delegation to the Halifax International Security Forum in Canada this weekend, and something spectacular happened. The two senators engaged in a far more amicable conversation than would have ever been seen in the Sunday news shows, from grilling of witnesses in committees, or with reporters chasing them down the corridors of Congress.

Why, at this conference, some 800 miles outside of Washington, D.C. the Republican and Democrat even allowed themselves to express some optimism.

"I'm very optimistic about the future of the United States of America. We're going to be energy independent, manufacturing jobs are coming home, we are seeing a steady improvement in our economy," McCain said, even as he expressed concern about the place of America on the world stage.

Kaine picked up the former sentiment, arguing against the notion that America is on decline.

The United States is experiencing the longest stretch of jobs growth in the history of the nation, and the Dow Jones closed at a record high, the Virginia Democrat said. It's also become the largest energy producer in the world, even while reducing greenhouse gas emissions. In Afghanistan, the United States has contributed to increasing life expectancy from 44 years to 61 years. And its military destroyed a large portion of Syria's chemical weapons stockpile.

“A negotiation over the Iranian nuclear program, an attempt to find a better government in Iraq, an attempt to find a coalition government that will work in Afghanistan -- these are happening because of the United States,” Kaine said.

And there was not just occasional agreement, but also the camaraderie that old-timey pols from decades past like to reminisce about. On Friday evening, as the conference got underway, the two senators were on the stage delivering comedic standup routines. By Saturday afternoon, they both appeared for a panel about the United States' role in the world, wearing matching lobster lapel pins (the crustacean is a local culinary highlight).

The two senators found common ground on the need for Congress to pass a war authorization for continued anti-ISIS military operations in Syria and Iraq.

"You just can't have a war without Congress," Kaine said. "You can't ask people to risk their lives, risk getting killed, seeing other folks getting killed or injured if Congress isn't willing to do the job to put their thumbprint on this and say, this is a national mission and worth it."

McCain and Kaine were on the same page on the need for a war authorization, even if they differed on whether Syrian regime change should be a formal part of American foreign policy.

"[Obama] should have brought an authorization to us, and let us on [the Senate committee on] foreign relations debate… We shouldn't have adjourned for seven weeks before the midterm election, with a war going on and no vote," Kaine said. "It's ridiculous."

Added McCain: "I totally agree with Tim, and I do think it's very important for the president to come over with the authorization that he wants. And that hasn't happen. Every time I've been involved with these… [the White House] has come over with their outline, and we've debated and amended, and that hasn't happened."

It wouldn't be a lively discussion without a few jabs. But by and large, McCain and Kaine didn't so much disagree as lament different topics. The Arizona Republican railed against the administration’s strategy on Ukraine, while the Virginia Democrat explained his opposition to the Keystone XL pipeline.

Kaine was frustrated with the brokenness of the legislative process in Washington, while McCain said leaders shouldn't heed public skepticism of war ("It's all about leadership, all about presidents who can talk to the American people and explain to them the challenges we face," he said).

All in all, it was a chummy conversation, held far from the partisanship of America’s capital. The two senators led the American congressional delegation to the annual national security conference, which takes place annually in Halifax. The delegation also included Sens. Ted Cruz and John Barrasso; Senator-elect Tom Cotton; and Reps. Adam Schiff, Tom Pompeo, Tulsi Gabbard and Adam Kinzinger.