The path to an escalation of conflict in the Middle East could be very short
In a military strike like the one being discussed by the US and its allies, every type of bomb and every type of target carries a message.
However while the language of violence in the Middle East has been finely calibrated, over decades of bloody trial and error, the route to escalation is very short.
Beyond obvious causes, like a mistake involving Russian casualties, other deliberate and carefully calculated acts are also risky.
Facilities allegedly used to manufacture chemical weapons are a likely target of Western strikes against Syria.
French President Emmanuel Macron has said his country is prepared to strike such facilities, but which ones?
After Syria admitted to its chemical weapons program in 2013, the Organisation for the Prohibition of Chemical Weapons said it couldn't be sure Syria wasn't hiding something.
Without offering any proof, Israel said this week that it believes Syria has resumed production.
But Mr Macron's assertion that France has "proof" chemical weapons were used last weekend in Douma is limited to the use of chlorine and, so far, does not include nerve agents like sarin, which were produced in the mainstream program
Striking locations used to weaponise chlorine, a simple industrial chemical much easier to handle than sarin, potentially opens up a much longer list of targets.
That's another path to escalation. The longer the list of targets, the greater the chance of an error or misinterpretation.
In a little-noticed declaration about the limits of French intentions, Valerie Lecasble, a spokesperson for the French Defence Ministry said: "The President specified that 'there would be no mission to attack the allies of the regime … but to attack the chemical capacities held by the regime'."
That's an acknowledgement of another path to escalation.
Concerns about Iranian presence in Syria
Apart from Russia, Iran has built up a significant presence in Syria.
That's what Israel — the most important US ally in the region — is most worried about.
And, while US President Donald Trump has been wildly erratic on Syria, many in his administration, especially newly appointed National Security Adviser, John Bolton, are determined to confront Iran.
If Iran is hit in a meaningful way it could perceive a longer-term threat to its own substantial investment in Syria and respond accordingly.
That could come in Syria's east, where US forces are stretched out along a vast swathe of territory from Manbij in the north, down to the Iraqi border.
Yesterday in Damascus, foreign policy adviser to Iran's Supreme Leader Ayatollah Ali Khamene, Ali Akbar Velayati, said: "East of the Euphrates is also a very important and valuable area.
"We hope next steps will be taken in order to liberate east of the Euphrates and expel the occupying Americans from that area."
Syrian forces could launch attack on Israel
A more troubling arena is in Syria's south where Syrian forces could fire into the Israeli occupied Golan Heights or into northern Israel proper.
It's all in very close proximity to southern Lebanon where the Iranian and Syrian backed militia Hezbollah has a formidable rocket arsenal aimed at Israel.
And any exchange between Israel and Hezbollah signals the likely start of a regional war in Syria, Lebanon and Israel, involving all parties active in Syria.
Mr Trump and his allies have many options and, paradoxically, the presence of the Russians and the Iranians in Syria should mean there is less fear of a "regime change" agenda than there was when strikes were discussed after the chemical weapons attack in 2013.
But there are also boundaries beyond which much more dangerous conflict becomes likely.
And just as a reminder of how tight those boundaries can be: an F16 war plane could fly low and slow from Syria's northern border with Turkey, to its southern boundary with Israel, over every major city including the capital Damascus to its southern border in less than half an hour.
At top speed, it would take less than fifteen minutes.