Blind partisanship is truly a sight to behold.

A lie over a rumoured game of hide-the-cigar and other party favours in the Oval Office once sent Republicans running for the articles of impeachment. These days, brazen presidential truth-fiddling over a $130,000 payoff to a pornstar in the closing days of an election draws nary a whisper of criticism from within the GOP. What's changed?

Hands down, you clever clogs — there are no points for guessing "the president's party affiliation." Nor do you score for pointing out that Donald Trump hasn't (yet) perjured himself. Had Bill Clinton committed Trump's sins he would have been: a) unbelievably happy; and b) garroted sans the blessing of the courts.

Not that partisans are in the habit of placing the shoe on the other foot; playing the counterfactual demands a level of introspection that doesn't exist in these rabid times. "What would we do if the other guys pulled the same stunt," is a sobering and unloved question. But if the answer is "lose our s--t," then mounting the barricades to defend your own side's perfidy probably isn't the right call.

Good answer!

Blinkered partisanship is a pain everywhere, but it's most acute in the United States. With their unflinching support for President Trump's daily festival of stupid, rank-and-file Republicans have been reduced to the status of contestants on the game show Family Feud who yell "good answer" even though cousin Mikey, with two strikes on the board, has just offered "monkey wrench" as an example of an item likely to be found in a woman's handbag. Welcome to politics in the early 21st century, where what's good for the goose is "STFU, you stupid snowflake" for the gander.

Meanwhile, here in Canada, the political chat shows are filled with MPs dying to defend the indefensible. The prime minister broke federal ethics laws for holidaying in secret on the luxury private island of a man whose foundation's hand was out to government? "Everyone, including the prime minister, is afforded the right to a holiday," comes the sanctimonious answer, as if the right to shore leave was the question. The party was caught taking cash for access to ministers? "We're proud to consult with Canadians," harp the backbench seals. And on it goes.

Here in Canada, the political chat shows are filled with MPs dying to defend the indefensible. (Sean Kilpatrick/Canadian Press)

It goes without saying the Liberals wouldn't have been so generous in their interpretations had the Conservatives been caught with their trousers down in this way. The same applies to the previous government as it defended its sins. Why can't partisans just say these kinds of episodes are a mistake not to be repeated and move on?

In a word: the internet.

The speed of the online realm not only forces partisans into millions of daily collisions, it also finds them an audience. No matter how craven your defence, or mindless your attack, someone on Facebook or Twitter will extol its virtues.

This wasn't typically the case when the public's business was transmitted to the people via intermediaries in the media. Trying to squeeze a shameless defence through the filter of the press was an unrewarding play, one that dented your credibility, so one was only offered in truly desperate times.

Nowadays, not only does the internet fail to reward conciliatory gestures, it actively punishes politicians for them. Add in a leader who apparently feels no shame, like Trump, and you begin to see how his method of unrelenting transgression without apology becomes a viable strategy.

Triggering partisan antibodies

With the influence of the press desperately low in certain areas, it also takes an unholy amount of effort to puncture someone's filter bubble. Many partisans no longer see or hear criticism of their leader or tribe.

The end result? We've arrived at the point where provoking serial outrage in observers and opponents is as important — if not more important — to one's re-election prospects than legislative accomplishment. The fury is what triggers the partisan antibodies you need to survive. It doesn't matter if the things Donald Trump says are at odds with the facts, as long as his words raise the ire of the "fake news media" then his supporters will give him a pass.

It's for the same reason Prime Minister Justin Trudeau has taken to saying Stephen Harper's name more than Laureen Harper does. With the accomplishment till looking a little empty, Trudeau is now borrowing from the bank of Liberal Harper hatred. And if Harper's name also prompts a reflexive gag in reporters' throats, then so much the better.

The only thing that will row these partisan habits back is more friendly fire. The leadership and the party's online ultras will hate it, but here the internet is an unreliable guide. Most voters don't follow along closely enough to score each transgression on Twitter, they just want to see someone to put their hand up when something goes pear-shaped and say, "Sorry we messed that one up, we'll try better next time."

Defending the indefensible might wire the case, but it is a game of diminishing returns — one that limits the possibility of a return to office.

So remember partisans, if it's not defensible when the other guy does it, that's your cue to start skewering your own side for doing the same, not to double down.

This column is part of CBC's Opinion section. For more information about this section, please read this editor's blog and our FAQ.