Greg Sheridan (“Bleeding hearts ignore the complexity of the asylum-seeker issues”, The Australian, 1/8) defends mandatory detention and other punitive treatment of asylum seekers on the ground of its purported deterrent effect on others who may contemplate dangerous boat journeys. He speaks of “the difficulty of the simple assertion that human beings must always be treated as ends in themselves, not means to influence other human being”, implying that this assertion is not always true.

The only real difficulty is defending this founding principle of the rule of law from the morally corrosive utilitarianism Sheridan advocates.

Breaching the bases of our own polity is not the only way to prevent deaths at sea; nor is a petty focus on repelling refugees from our own back yard without concern for what happens to them next. A good start would be for the world’s rich countries to cooperatively empty the refugee camps as enthusiastically as they helped fill them, a least until the average wait is reduced to months instead of decades. Until we do this, desperation will continue to drive people across the world, and Sheridan’s complaints about “procedural unfairness” and Islamists-under-the-bed will continue to sound like weak excuses for cruelty.