Earlier this week, Andrew Coyne mused on Twitter about how parties seek to make hay out of attacks by their opponents, with particular emphasis on the Libs' response to PC and Con attacks on their leaders in 1993 and 2004. But I'd think it's worth noting some distinctions between then and now which may make the tactic rather less effective than it might once have been - as well as discussing the circumstances where it might still work.
To start with, let's look at the threshold a party needs to cross to be seen as going too far - and how it may have been altered by the last decade in Canadian politics.
If the attacks mentioned by Coyne gave rise to a public backlash, it's surely because they represented a significant departure from what Canadians had seen in the time preceding them. In 1993, any political ads between elections would have been utterly unknown, making a seemingly personal image sprung without warning during a campaign look like something far beyond the realm of the familiar and acceptable. And in 2004, Stephen Harper's attacks on Paul Martin likewise came out of the blue.
But now, the situation is rather different - whether the consequence was intended or not.
The Cons' habit of launching personal attacks early and often might once have been explained by the instability of minority Parliaments. But they've continued the pattern throughout three terms in office including one as a majority government - meaning that few voters now figure to be taken by surprise. And the Cons can hardly be said to have been punished politically for doing so.
Moreover, especially over-the-top ads such as the glittery ones which mocked Justin Trudeau may actually leave room for campaign attacks to appear reasonable and measured by comparison.
I'd thus argue that the Cons have not only planted their specific messages in the public consciousness, but also substantially moved the bar as to what will actually inspire public outrage. (Indeed, the exact same charge which arguably hurt Harper in 2004 didn't seem to do much lasting damage to the Cons when it became part of their message while in power.)
Now, it's true that the Cons' credibility is in tatters - and it may be that attack fatigue represents a contributing factor. But there's a difference between weariness with an incumbent and a willingness to be outraged on behalf of a competitor. And while we can't rule out the prospect that something during the course of the campaign will still manage to cross a line which the public won't tolerate, we shouldn't be under the illusion that the line is in the same place now as two decades ago.