Is there any way of escaping the theatre of chemical weapons? First, Israeli "military intelligence" says that Bashar al-Assad's forces have used/have probably used/might have used/could use chemical weapons. Then Chuck Hagel, the US Defence Secretary, pops up in Israel to promise even more firepower for Israel's over-armed military – avoiding any mention of Israel's more than 200 nuclear warheads – and then imbibing all the Israeli "intelligence" on Syria's use/probable use/possible use of chemical weapons.

Then good ol' Chuck returns to Washington and tells the world that "this is serious business. We need all the facts." The White House tells Congress that US intelligence agencies, presumably the same as Israeli intelligence agencies since the two usually waffle in tandem, have "varying degrees of confidence" in the assessment. But Senator Dianne Feinstein, chairman of the Senate intelligence committee – she who managed to defend Israel's actions in 1996 after it massacred 105 civilians, mostly children, at Qana in Lebanon – announces of Syria that "it is clear that red lines have been crossed and action must be taken to prevent larger-scale use". And the oldest of current White House clichés – hitherto used exclusively on Iran's probable/possible development of nuclear weapons – is then deployed: "All options are on the table."

In any normal society the red lights would now be flashing, especially in the world's newsrooms. But no. We scribes remind the world that Obama said the use of chemical weapons in Syria would be a "game changer" – at least Americans admit it is a game – and our reports confirm what no one has actually confirmed. Chemical arms used. In two Canadian TV studios, I am approached by producers brandishing the same headline. I tell them that on air I shall trash the "evidence" – and suddenly the story is deleted from both programmes. Not because they don't want to use it – they will later – but because they don't want anyone suggesting it might be a load of old cobblers.

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CNN has no such inhibitions. Their reporter in Amman is asked what is known about the use of chemical weapons by Syria and replies: "Not as much as the world would want to know … the psyche of the Assad regime …." But has anyone tried? Or simply asked an obvious question, posed to me by a Syrian intelligence man in Damascus last week: if Syria can cause infinitely worse damage with its MiG bombers (which it does) why would it want to use chemicals? And since both the regime and its enemies have accused each other of using such weapons, why isn't Chuck as fearful of the rebels as he is of the Assad dictatorship?

It all comes back to that most infantile cliché of all: that the US and Israel fear Assad's chemical weapons "falling into the wrong hands". They are frightened, in other words, that these chemicals might end up in the armoury of the very same rebels, especially the Islamists, that Washington, London, Paris, Qatar and Saudi Arabia are supporting. And if these are the "wrong hands", then presumably the weapons in Assad's armoury are in the "right hands". That was the case with Saddam Hussein's chemical weapons – until he used them against the Kurds.

Now we know that there have been three specific incidents in which sarin gas has supposedly been used in Syria: in Aleppo, where both sides accused each other (the hospital videos in fact came from Syrian state TV); in Homs, apparently on a very small scale; and in the outskirts of Damascus. And, although the White House appears to have missed this, three Syrian child refugees were brought to hospital in the northern Lebanese city of Tripoli with deep and painful burns on their bodies.

But now for a few problems. Phosphorus shells can inflict deep burns, and perhaps cause birth defects. But the Americans do not suggest that the Syrian military might have used phosphorus (which is indeed a chemical); after all, American troops used the very same weapon in the Iraqi city of Fallujah, where there is indeed now an explosion of birth defects. I suppose our hatred of the Assad regime might better be reflected by horror at reports of the torture by Syrian secret policemen of the regime's detainees. But there's a problem here, too: only 10 years ago, the US was "renditioning" innocent men, including a Canadian citizen, to Damascus to be interrogated and tortured by the very same secret policemen. And if we mention Saddam's chemical weapons, there's another glitch: because the components of these vile weapons were manufactured by a factory in New Jersey and sent to Baghdad by the US.

That is not the story in our newsrooms, of course. Walk into a TV studio and they're all reading newspapers. Walk into a newspaper office and they're all watching television. It's osmotic. And the headlines are all the same: Syria uses chemical weapons. That's how the theatre works.