Contrary to what is now accepted wisdom, the Liberal Party's leadership problems did not begin when St ©phane Dion was unexpectedly handed the party's crown 18 months ago. They began when the Conservative Party told us over and over that Dion is "not a leader" and Canadians, including many Liberals, started believing the claim.

Similarly, the Liberal Party's problems with a carbon tax -- that is, its inability to sell Canadians on its merits -- doesn't stem from the fact that it's a bad idea. The problem is that the Liberals can't seem to sell a carbon tax, just like they can't seem to sell their leader, to a skeptical electorate. That in turn makes it easy for the Conservatives to dismiss the idea as some hare-brained plot to part Canadians from their hard-earned money.

It is that incentive that the Dion must sell to Canadians. If he fails to do so -- or worse, if he nixes the idea in the face of sustained criticism -- then all he's doing is proving correct those who insist he's "not a leader."