As a general rule, a public figure cannot become a polarizing figure without having done or said a great deal, or, at an absolute minimum, without having done or said at least one extra-ordinary thing.

But that rule, like others, doesn't apply to Justin Trudeau.

Four years ago, first when Barack Obama became the Democratic nominee for president, then again when he won the election, there was a wave of commentary about how much the United States, and the whole Western world, had changed for the better. The scourge of racism, the subjugation of women, the marginalization of the disabled, the persecution of gays and lesbians: All this had diminished - not vanished, but diminished - in such a short time.

The morning after a man opened fire at a Parti Québécois rally, killing one person and injuring another, we knew the police had arrested a man at the scene. We knew the man had worn a ski mask and a bathrobe. We knew he was 62 years old, lived in Quebec, but was not a Montrealer. And there were reports that he had ranted "the Anglos are waking up," among other, angry, political statements.

So we knew next to nothing. We didn't even know the man's name. And yet many people immediately turned to Twitter, blogs, and news-paper websites to express what they were sure of.