Who is part of the "International Community"? What is the origin of the terminology and who "controls" its usage?
Smacks of the lingo used by people who celebrate the international market, which coincidently has played some part in my household contributing to the soaring numbers of international unemployed.
I think it depends who's saying it and in what context. Mainstream international relations theory is split between 'neorealists' and 'neoliberals'. The neorealists tend to deny there's such thing as an international community, only individual nation states pursing their national interests. They'd see appeals to 'the international community' as cynical realpolitik, trying to present national interests as universal interests. Neoliberals tend to see more scope for international co-operation (UN, WTO, other institutions) and would tend to be referring to such international institutions and their common aims as 'the international community'.
So who gets to be part of the club depends on who's talking. Typically, it only applies to nation states (hence discussions about whether Palestine is part of the 'international community'), but may also include international institutions and in some contexts maybe other actors (Transnational Corporations, NGOs - normally seen as part of 'international civil society' though). Generally it would probably refer to any state who's part of the UN, but it also has the cynical realpolitik side to it, so 'the will of international community' is often invoked in support of the invasion of Iraq, even though most of the world's states didn't really support it.
In terms of more radical theory, again it would depend who's saying it. Negri & Hardt would probably be referring to 'Empire' (which isn't dissimilar to the neoliberal view of the UN, WTO, TNCs etc). Other Marxists might use something closer to the neorealist definition, where it's something to be put in inverted commas as it's more rhetoric than reality, presenting competing national interests as for the common good.
From what I've seen of its use by the media in the UK it usually means the imperialist interests of the USA, the UK, France and Germany.
Just a precision on the above: from my observations smaller imperialisms can become part of the "international community" but this usually needs the backing of one of the larger imperialisms above, ie, it is in the latters interests - the whole of the international community (the major western imperialisms) don't necessarily have to agree on this, in fact there can be strong disagreements (imperialist tensions).
To give some concrete examples: Gadaffi's Libya was not part of the "international community" but Tony Blair's embrace signalled it was "in the fold" - then it wasn't, now it is again.
Qatar could be part of the "international community" as could other smaller powers depending on the services they offer to the larger imperialisms. Burma is now applying itself to become part of the "international community" with its rapprochement towards the USA, Britain and France. It is not yet part of this community.
Turkey, in my opinion, is a bit in and out of the "international community" but at the moment it is very much in, particularly given its use by the US in allowing American and British special forces onto it border regions in order to back up the "Free Syrian Army". Syria, it goes without saying, is not part of the international community and neither is Iran.
The 'International Community' in contemporary modern terms usually refers the the semi-globalised state we are currently in, which has been shaped by dominant state-market collaborations and general neoliberalism. However, the actually existing 'international community' realistically refers to a regionalised triad of economically potent nations. I.E NAFTA, the EU and growingly the newly industrialised countries in Eastern Asia. Specifically it refers to the U.S, China and the E.U as a supranational bloc.
Basically, the international community is the economically potent nations and simultaneously those most pragmatic to trade with.