A one-time Crown attorney who rose to the rank of justice minister and attorney general of Canada, MacKay announced Friday he won't seek re-election in his Nova Scotia redoubt after 18 years as a member of Parliament.
The perennially youthful cabinet jock turns 50 in late September, about the time he and his wife Nazanin Afshin-Jam are expecting their second child.
"Nothing humbles you, grounds you, or focuses you more than children," MacKay told a gathering in Stellarton, N.S. "I thought that as I was wiping milk off my suit to come here."
It marks the end of a long and under-examined alliance with Stephen Harper, with whom MacKay — as the newly minted Progressive Conservative party leader — completed a merger deal in October 2003, just six months after winning the PC leadership on a bargain that explicitly precluded any dalliance with Harper's Canadian Alliance.
Two weeks after winning the PC crown, MacKay yukked it up at the annual Parliamentary Press Gallery dinner at his own expense: "I've been called treacherous, stupid, venal, lazy ... and that's only by the Tories!"
Since 2006 he's held the most senior roles in Harper's Conservative cabinets — foreign affairs, national defence, justice — yet was not publicly perceived as an influential heavyweight in the inner workings of the tight Conservative power structure.
Rather, it was MacKay's breezy personality and aristocratic good looks — and a passion for rugby — that seemed to define him.
He was voted "sexiest male MP in the House of Commons" six years running by the Hill Times, an inside-the-Queensway politics trade newspaper. His periodic paramours made national news.
Name another Conservative who's graced the cover of Hello! Canada, whose usual fare runs to the royal family, George Clooney and Avril Lavigne. MacKay did it with his glamorous Iranian-born wife and their son Kian.
His breakup with fellow MP, Liberal floor-crosser and Magna auto parts heiress Belinda Stronach in 2005 was the stuff of romantic farce — complete with a mournful photo-op with a borrowed dog on a Nova Scotia farm.
And his flirtatious banter with Condeleeza Rice, then the U.S. secretary of state, wagged chins all the way to Washington.
The son of Elmer MacKay, a former minister in the government of Brian Mulroney, Peter was somewhat to the manor born.
He was raised in rural Nova Scotia and, later, Ottawa, an idyllic childhood that came complete with some time being educated in a one-room schoolhouse.
After winning a seat in Parliament at age 32, his run for the Progressive Conservative leadership in 2003 caught no one by surprise. He was the establishment front-runner throughout.
The leadership win is best remembered for the no-merger pact he made (and quickly broke) with dark-horse contender David Orchard. But it's worth noting it was Jim Prentice whom MacKay defeated on the fourth ballot.
Prentice, like MacKay, went on to become a Harper cabinet minister before leaving for private life as a bank executive — and then a brief, unsuccessful stint as Alberta premier which ended in electoral disaster earlier this month.
MacKay didn't run for the leadership of the newly merged Conservative party, and he has served as a loyal lieutenant to Harper despite some tempestuous portfolios.
When Ben Harper, the prime minister's eldest child, was small, MacKay used to take him to hockey practice if dad couldn't.
Harper flew to Nova Scotia for Friday's announcement and expressed genuine warmth for MacKay's family friendship.
"For a long time with Ben it was just Peter MacKay this, Peter MacKay that all the time," quipped Harper. "So much for dad the prime minister."
But MacKay has made news too often for contretemps, including a flight from a private Newfoundland fishing lodge aboard a coast-guard search-and-rescue helicopter and an ugly, public bun fight with the chief justice of the Supreme Court over an inadmissable court appointee.
Still, MacKay leaves politics relatively unscathed and remains a potential Harper successor as Conservative party leader.
"This is not goodbye, this is farewell," he said at the end of an emotional 20-minute speech, before imparting a bit of recent advice from his father Elmer.
"'Never lock a door when you leave unless you have to.' Sage advice."
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