Which way is the enemy?

On Sept. 18, more than 800 Australian police officers in three jurisdictions (federal, Queensland and New South Wales) conducted a series of counter-terrorism raids in Brisbane and Sydney to foil a plot by supporters of the Islamic State of Iraq and Syria, also known as just the Islamic State.

Prime Minister Tony Abbott, backed by opposition leader Bill Shorten, has been calm, confident and reassuring in describing the threat and the steps being taken to deal with it. This extends to Shorten supporting Abbott in the deployment of Australian military forces as part of a growing international coalition to take war to Islamic State.

The military response to Islamic State is unexceptionable in principle, given their existential threat to Iraq, ideological threat to religious pluralism, and celebration of "the extravaganza of brutality" in the words of U.S. Secretary of State John Kerry. Action against it is also uncontroversial in Iraq at the government's request. Action in Syria however raises legal difficulties.