An interesting question for history is who was the real leader of the West the past half-dozen years, Angela Merkel of Germany or Canada’s Stephen Harper, voted out this week after almost 10 years as prime minister. His great success was in helping bring his country through and past the global meltdown of 2008. He was loyal to Western principles and a friend of America even when, as in recent years, its leaders’ decisions left him doubting and dismayed.

A general rule of politics: After 10 years they are going to throw you out. But the vote was overwhelming after a charmless, dour campaign. The incoming prime minister is the 43-year-old son of charismatic former Prime Minister Pierre Trudeau. Justin Trudeau has been a snowboard instructor, schoolteacher, bartender, bouncer, speaker on environmental and youth issues, and advocate for avalanche safety. Sensing “generational change” and gravitating toward “a life of advocacy,” he entered politics and served two terms in Parliament. He has been head of the Liberal Party two years. He is handsome, has a winning personality, exhibited message discipline during the campaign, and is a talented dancer. There’s a sense we in the West have entered a new screwball phase. Watching Mr. Trudeau’s victory speech, I remembered the columnist Dorothy Thompson reaction on watching the newly inaugurated President John F. Kennedy. There’s something not fully stable there, she thought. But we have to let history do what it enjoys doing, which is surprising us.