Any decision to launch air strikes on Syria will be based on a full and proper legal grounding, says Attorney-General George Brandis.
The doctrine of collective self-defence could provide sufficient legal basis for the strikes, Senator Brandis said on Tuesday before a National Security Committee meeting to discuss the issue.
“As a matter of general principle, the doctrine of collective self-defence … can extend in an appropriate case to dealing with aggressive behaviour from behind the borders of neighbouring states,” he told Sky News.
Senator Brandis said that was the legal basis for Australia’s involvement in Iraq at the invitation of the Iraqi government.
It can apply where the government of a neighbouring state has proved unwilling or unable to deal with aggressive behaviour from within its territory.
“ISIL (Islamic State of Iraq and the Levant) does conduct aggressive attacks on Iraq from bases within Syria. We know that and we know that the government of Syria hasn’t dealt with that through unwillingness or inability,” he said.
Senator Brandis said there is abundant evidence that Islamic State operatives, including Australian Neil Prakash, have been active in encouraging terrorism in Australia.
“We are at war with ISIL,” he said.
Senator Brandis said there is an expectation that the government will give the go-ahead but no decision has yet been made.
The National Security Committee is meeting on Tuesday night, with the expectation the cabinet will give final approval at its meeting on Wednesday morning.
Former US General David Petraeus, in Australia as a guest of the Lowy Institute for International Policy, said he had commanded Australian forces in Iraq and Afghanistan.
He said Australia is a middle power but it punches at the heavy and super-heavyweight level, and any additional contribution will be welcomed in the coalition.
“The quality of your individual soldiers, diplomats, intelligence professionals, the professional expertise of your conventional and special operations units, is truly extraordinary,” Mr Petraeus said.
Opposition Leader Bill Shorten wants to know the endgame for the government’s strategy in Iraq and Syria.
“It’s important that we also understand that you’re not going to drain the swamp of terrorism just by military action alone,” he told ABC radio.
Foreign Minister Julie Bishop said the exit strategy is when Islamic State is prevented from carrying out attacks on the civilian populations in Syria and Iraq.
Greens leader Richard Di Natale said his party will oppose any extension of Australian operations, saying aerial bombardments risk killing civilians.