Via Instapundit, this worry is a bit too much to take seriously:
Turkey's intensified role in the crisis is raising serious concerns that the country, a member of NATO, may ultimately drag the rest of its partners into war with Syria by invoking Article Five, which stipulates that all alliance members must come to the defense of any other member country that has been attacked.
Occasional mortar hits are a far cry from being attacked; and a Turkish invasion of Syria is a far cry from defense against an attack.
As for Turkey invoking the alliance, no country has that power. Any country has the right to determine how it meets its alliance duties to come to the defense of a member country that has been attacked.
Turkey did not, I'll remind you, send forces to fight Libya last year.
So Turkey can call NATO for help.
And maybe France and Britain send their combined naval task force; maybe we send an air expeditionary wing and AWACS and refueling aircraft to participate, and send a heavy brigade to act as a reserve inside Turkey in case we need to spearhead a drive on chemical weapons sites; maybe Norway sends a few aircraft to fly patrols over Turkish territory; maybe Germany registers disapproval of the whole thing while letting their staff officers assigned to NATO remain at their desks in the NATO bureaucracy that might assist Turkey; and maybe the rest of the alliance replenishes Turkish ammunition stocks with their own production and war reserves (if any exist after the Libya War).
Otherwise, Turkey has the military power to pound Syria all on its own. Greece isn't going to side with Syria. Russia isn't about to invade in response. And Iran isn't really a military factor as long as it doesn't have nukes.
But there is no automatic alliance machine that can be triggered into launching a regional war the way the alliance systems contributed to war in 1914 over a minor incident.
Indeed, if the worry is that Syria will use chemical weapons on the battlefield against the Turks, lack of full NATO response would be a plus.
Syrian use of chemical weapons would surely compel a lot more help for Turkey than Turkey gave to NATO in the Libya War. so if NATO help is limited and then Syria uses chemical weapons, a world of hurt descends on Assad.
Heck, it might be a useful test to see if a nuclear-armed NATO alliance can deter Syrian use of WMD. I doubt Iran would like to see that Western excuse for inaction with Iran proven wrong.
War with Syria may or may not be a good idea. But the idea that it triggers anything big is wrong.