The political truism is that “change” is good. Except when change isn’t the kind of change voters want, in which case change is bad. Got that?

It’s not an idle question. There are, or have been, a bunch of federal, provincial and territorial election campaigns taking place this year. In each one, the concept of “change” has or will be a factor.

The reason why you hear about change so much during election years is simple: It’s a simple, inoffensive way of saying “throw the bums out” — we want a new direction, new faces, new energy. It’s a powerful message, too.

Brian Mulroney rode “change” to a massive victory over the tired old Grits in 1984. Jean Chretien rode “change” to a massive victory over tired old Tories in 1993. Stephen Harper’s win in 2006 wasn’t massive, but it had everything to do with change. Barack Obama was arguably the most successful “change” campaign ever — he crushed Republicans across the U.S. People wanted change, people voted for it.

Ontario Premier Dalton McGuinty also greatly benefited from change in 2003, when his campaign slogan was “Choose Change.”

Now, in an ironic twist, his principal opponent has branded his campaign document — complete with colours, font and stylistics that should have Facebook lawyers reaching for the phone — “ChangeBook.”

So, as a message, change works. But when doesn’t it work? When you are the incumbent, that’s when. In campaign 2011, Harper was the guy who had been in office for half a decade — for good and bad. During his time in office, there’d been no shortage of scandals, ministerial resignations and assorted bad news stories.

But despite all that, Harper won a bigger victory than he had in 2006 and 2008 — and he finally secured his much-lusted-after Parliamentary majority. How come? Why didn’t people heed then-Liberal leader Michael Ignatieff’s daily call for change?

Two reasons. One, Canadians generally felt Harper had done not-badly in the aftermath of the 2008-09 global recession. They looked around and saw that we generally fared better than the Europeans and the Americans. So that helped.

Two, sometimes change is not what voters want. Harper knew this. Every day, in every press encounter, he hammered away at the notion that the election was unnecessary — and, most significantly, that change was risky during troubled economic times. Canadians, he said over and over, need stability and a steady hand in times like these. Canadians agreed. That’s why recent events are political gold for any politician seeking re-election. The European debt contagion is spreading; the U.S. government came close to default due to Republican gamesmanship; the markets have been chaos for weeks.

All of it comes together to present a future that looks dangerous and uncertain. Thus, the winning Harper (and McGuinty, and Obama, and so on) message: “We’re turning the corner. Do you really want to gamble away all that we have achieved? Do you really want to roll the dice with inexperience and undefined change?”

Like I say: Change works.

Except, as in times like these, when it won’t.