If the former think advancing a subject might mean more votes, they declare that "the people of Canada are concerned." Journalists then decide whether it'll sell papers, to use an old term. If the subject clears both bars, it's a campaign issue.
That entire process took place with remarkable speed last week. The subject of Canadian arms sales to Saudi Arabia was raised, became an issue and died, all within about 24 hours.
The revenant Bloc Quebecois leader, Gilles Duceppe, who has suddenly taken a great interest in anything pertaining to radical Islam, kicked things off during the French-language leaders' debate last Thursday.
"As we combat ISIS," he asked Stephen Harper, "We must realize that its ideology was financed and promoted by Saudi Arabia, and we are sending billions worth of arms to Saudi Arabia.
"Would it not be sensible to say that's enough, we're stopping arms sales to Saudi Arabia? Wouldn't that be logical, given our fight with ISIS?"
Harper, a man who has portrayed his government's foreign policy as more principled and less susceptible to the power of the almighty dollar than other governments, basically replied that there's a lot of money at stake and thousands of jobs in London, Ont.
The contract to export $15 billion worth of armoured vehicles to the Saudis, he noted, is the largest in Canadian history.
Cancelling it would only punish Canadian workers, he said, and besides, the contract is "support for an ally."
"Yes, Saudi Arabia is a great ally," snorted Duceppe. "Wonderful. I've taken note."
Allied with whom
By the next day, the subject was a hot candidate for campaign issue-hood. Journalists were pursuing it with Harper.
For a brief, fascinating moment, it looked like we might actually be having a real national discussion about Canada's embrace of a bellicose, misogynistic, medieval theocracy that has a nasty habit of shoving cash into the pockets of those Stephen Harper would call "jihadi terrorists."
Here are a few things we could have explored:
To start with, the Canadian government must, by law, seek assurances from any country with a record of human rights abuse that it will not use arms exported from Canada against civilians.
But, as University of Ottawa professor Roland Paris notes, "We don't know whether assurances were obtained from the Saudis. We've allowed an arms sale to trump human rights."
The reason for the lack of disclosure would appear to be pretty simple: the Saudis have demanded secrecy, and Conservative ministers were instructed accordingly.
Something else: As Duceppe correctly pointed out, the objective difference between our allies, the Saudis, and ISIS is blurred.
Despite now being part of the anti-ISIS coalition, the Saudis have provided extensive support to the group in the past, and have funded extremist madrassas (schools) and mosques worldwide over the years.
In fact, 28 pages of the U.S. Congress's report on 9/11, which remain officially suppressed, are widely believed to accuse high-ranking Saudi officials of providing consular and financial support to the hijackers, the vast majority of whom were Saudis.
But the Saudis have oil, and they sell it cheaply, so the White House, like Stephen Harper, tends to take a pragmatically sympathetic view.
Here's another thing we could discuss: Like ISIS, the Saudis are champion torturers and beheaders.
By some estimates, the Saudis actually outdo ISIS. They behead for imagined apostasy and for general criticism, but also for sorcery and a list of other offences. And after beheading, the Saudis sometimes crucify the body.
They're scheduled to do just that in the days to come with Mohammed al Nimr, 21, who was arrested four years ago for advocating on behalf of Shia rights.
The ruling Sunni family despises Shia Muslims, and mercilessly oppresses them.
If you can stomach it, go watch the video secretly recorded and uploaded of Saudi officials hacking the head off a Burmese woman accused of raping her husband's daughter with a broom handle.
Extremely uncommon, a woman raping a child with a broom handle, but someone had to be punished, and Laila Bint Abdul Muttalib Basim died shrieking her innocence.
Despite all this, the Saudis are often portrayed by Western allies, like Canada, of being a force for stability in the region.
In pursuit of that stability, though, they've armed and financed al-Qaeda affiliates not just in Syria but in bordering Yemen, specifically tribes sympathetic to al-Qaeda in the Arabian Peninsula.
Saudi bombing missions in Yemen, ostensibly to restore the government and keep Iranian-backed Houthi rebels from advancing, have killed thousands of civilians.
And in Bahrain, where Saudi troops arrived during the so-called Arab Spring in armoured vehicles like the ones they're buying from Canada, they helped violently crush Shia Muslims demanding more rights.
Dancing in the desert
So. Why did Canada's arms sales die so quickly as a campaign issue? It wasn't even raised in the foreign policy debate a week later.
Well, our main party leaders really don't want to talk about it. Justin Trudeau simply evaded the question during the French debate.
Tom Mulcair went a bit further, saying Canada should study a country's human rights record before approving arms sales, and was promptly asked by a large industrial union involved in the contract, Unifor, to please shut up.
("We asked the NDP to not make this an issue, that it be kept under wraps," said Fergo Berto, Unifor area director for London.)
But what really killed it the issue was the apparently widespread belief among Canadians that the Saudis are somehow moderate.
After all, former U.S. president George W. Bush was photographed holding hands in pubic with the late Saudi king Abdullah in 2005, and Barack Obama appeared to bow before him four years later.
Justin Trudeau's father danced in the desert with Sheik Yamani, the Saudi oil minister, in 1980.
The Saudis were even just awarded a prominent position on the UN Human Rights Council.
Human rights advocates thundered outrage. But Canada, in the past a pitiless critic of the council, maintained a respectful silence. After all, the Saudis are allies.
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