You’re missing the point. The contention isn’t the legality, it is that the policy is going to result in mass death in the face of the climate change refugee crisis. The logical outcome of the Pacific Solution in the event of a Syria-like human wave unto Australia is hundreds of thousands of men women and children being locked up in Australian detention camps. Think about that for a moment, Nauru is already a tragedy for the few locked up there - imagine what it would be like with a population the size of Toowoomba. The rest will be dead at sea as they try to reach Australian shores. You can hide behind the legality but it doesn’t make it moral.