In this context, the Canning by-election could have been called the Cunning by-election.

It gave a clear, vindicating victory for Malcolm Turnbull's brazen, lightning coup. 

So now the vultures will soon be hovering over the obvious loser, Bill Shorten, who made a serious blunder last week that puts him on carrion watch.

He just became much more vulnerable. He has never been popular in the opinion polls.

He has rarely been impressive in parliament. He was especially unimpressive in the three sitting days leading up to the Canning by-election.

On Tuesday, in his first question to the new prime minister, Shorten finished with this: "Will the prime minister change the substance of this government or is it just about its style?" 

He concluded his second question with, "Will the prime minister change the substance of the government or just the style?"

The spectacle was unedifying. The signal was wrong. The public is sick of smearing. 

The tone and the tactic made Turnbull appear statesmanlike, in contrast to Shorten. He also had an effortless retort to every insult: under the cabinet system he is bound by the government's decisions.

The next day's questions were equally unedifying. Shorten, asking about climate change policy, ended with, "Has the prime minister sold out his principles to achieve his personal ambition? "

The next day, Thursday, was also devoid of substance and completely insular. Shorten's first question: "Even though there is a new Liberal leader, it is the same policies, the same chaos and the same division?"

This fusillade of sneering, led by the man who helped depose both the Labor prime ministers he served under, flagged Labor's tactics for the next year. They will keep it nasty and personal.

This is risky, given the public mood. It compounds the risk Shorten has taken in committing Labor to opposing the Free Trade Agreement with China, Australia's largest trading partner.

 If Labor, acting at the behest of the narrow self-interest of several unions, were to succeed in derailing, or even merely delaying this pact, the ramifications would be significant.

Labor's policy has to be a bluff. It can't be more than electoral scare-mongering and debt-repayment to certain unions. 

And the union that is leading, and financing, the attack on China is the Construction, Forestry, Mining and Energy Union.  

Eventually, the public is going to wake up to the recklessness of the CFMEU. In the past two years it has racked up $20 million in fines, legal bills and damages awarded. 

More than 60 of its officials are facing litigation.

If the public ever connects the dots, Shorten will become political carrion. 

He has 10 months to navigate the risks before the 2016 election campaign. It will be victory or death.

In the past week, Anthony Albanese, who narrowly lost to Shorten in Labor's leadership ballot in 2013, has suddenly been invigorated, jumping to his feet in the parliament and giving numerous interviews. 

Not all the vultures are perched up in the parliamentary press gallery and beyond, sniffing the wind.

- Paul Sheehan is a Fairfax Media columnist