....While in this case the western countries have been itching for direct intervention ever since this civil war started.
I would hardly say the US has been itching to get involved, anything but, and in truth they are the only people who can militarily make a difference (or better still if China & Russia immediately stop their support of the odious regime that could be a gamechanger)
The only people who seem to be itching (as you say it) to intervene currently are the French, who on their own, will likely do very little except bomb Assad with leaflets on existentialism, mime outfits and old records of Sacha Distel. They have few assets in theatre that could do anything other than pinpricks on the hide of an elephant though it might make them feel good about themselves but remember they too turned a blind eye to Saddam and his use of chemical warfare.
And as far as Liberal Interventionism is concerned, modern sensibilities and the sheer expense of defence budgets mean that few democracies possess the ability either in assets or the will of their population to go it alone and intervene in a conflict such as this and to be effective and have a favourable outcome with minimum loss of life.
Other than the US (and to a lesser extent Israel), they can only act in concert with others in a complimentary alliance of forces and intelligence.
You see also that this is not Libya with convenient Italian airfields close by.
To be effective against Assad and his forces, you need either Aircraft carriers (the French one is not too reliable, propellors dropping off and such, and its strike wing on its own would be inadequate other than a show strike), or handy land bases in a friendly country nearby together with in flight tanker facilities, especially if any useful load is to be carried by the sort of aircraft anyone other than the US and Russia possess. I suppose at a push, the French could attempt to use Lebanese bases for any
Force de Frappe though that would be fraught with all kinds of problems, it smacks of old colonialism and it would be an enormous stick in a hornets nest.
It's also improbable that UK bases in Cyprus could be used by them without all kinds of difficulties too and it's unlikely Turkey would allow their bases to be used unless the US gets involved and even then, I expect they will be very reluctant to have a couple of million more refugees flooding across the border.
And despite noises from Hague, forget the UK being involved in any significant game changing way, We can't afford it and also we can't unilaterally do much anyway these days without substantial US involvement. All we can do is perhaps provide the catering, some guidance on outsourcing and privatisation of public utilities, and as an afterthought perhaps park HMS Ocean somewhere offshore with a handful of Apaches on it. Without things like RC-135W Rivet Joint(not due in RAF service until December) and other appropriate modern intel gathering aircraft, I certainly wouldn't want to be flying into a very hostile Syrian airspace that has excellent anti aircraft defences (just ask the Israelis) in just a helicopter. I somehow doubt Harry for instance will get sent there.
So without a substantial Alliance of countries and their combined military assets, the options for intervention are realistically pretty limited. And so to repeat, the only people who could perhaps make a real difference are the US and so far there has been little to no enthusiasm from them for getting involved in any shape or form other than perhaps ensuring containment of the conflict within the borders of Syria.
Until the US change their mind, something I just don't see happening yet if at all, this will likely run and run with much huffing and puffing and ultimately empty rhetoric from assorted worthies here in Europe, and countless more deaths of civilians in Syria.
It's totally shit and it's the modern world and there seems little that we can actually do about it other than weep.