Chris Matthews, excitable liberal host of MBC’s “Hardball,” is instantly recognizable — and not just because of his impish face and floppy hair. It’s Matthews’s irrepressible manner that really signals it’s him. He is relaxed and interested and unabashed about asserting his opinion on anything and everything — his “takes,” as he refers to them, gained over the course of an engaged life spent close to the center of American politics.

Matthews joined the Peace Corps in 1968 and served two years in South African Swaziland. He became a Capitol Hill police officer, then a congressional staffer. Eventually, he wrote speeches for President Jimmy Carter and, during the Reagan years, was chief of staff to Democratic Speaker of the House Tip O’Neil.

At one point last Thursday evening in Denver — where Matthews was serving as moderator for a 9/11 commemoration debate on national security and the 2016 presidential election — former Mississippi Gov. Haley Barbour, a panelist, was waxing nostalgic about Ronald Reagan.

“Reagan inherited a recession from Carter, but he never talked about Carter. He tackled it. He compromised with Congress. He got things done,” Barbour said, referencing the politics of division that have marked the Obama era.

“Wait a second,” Matthews sputtered. “Reagan never talked about Carter? I was there… Of course he talked about Carter. ‘Are you better off now than you were four years ago?’ Remember that?” he said referring to a famous Reagan campaign line. “You don’t remember that? It was brilliant.”

The retort was signature Matthews: animated, entertaining and knowledgeable — with Matthews himself playing at least a supporting role in the tale.

Earlier in the evening Larry Mizel, founder of Denver’s Counterterrorism Education Learning Lab, the main sponsor of the 9/11 commemoration event, jokingly introduced Matthews as “the softball on ‘Hardball.’”

“Where would I be without you, Larry?” Matthews responded quickly, his arms folded across his chest, his tall frame bending out toward the crowd from behind Mizel at the front of the room. The exchange was fast and good-humored and it suggested that Matthews and Mizel were on casual terms. The audience laughed.

“Are you taking pictures,” said someone at a cocktail table to one of the photographers at the event. “You just gotta get a shot of me with Chris Matthews. Wait ’til he makes his way over here, OK? OK?”

— john.tomasic@gmail.com