Once upon a time terrorists had a code of honor; the targets selected for assassination were kings, ministers, generals or police chiefs.

When in 1904 a group of Russian revolutionaries went out on a mission to kill a certain grand duke, they canceled the action at considerable risk to their own lives because the duke traveled with his wife and his small children and there was the danger that innocents would be hurt. This historical incident inspired Albert Camus to write one of his best known plays.

Contemporary terrorism has not just become indiscriminate, there seems to be a particular temptation to single out innocents, partly no doubt because these are much easier targets than well-guarded public figures. Terrorists, such as the Chechens who took schoolchildren as hostages, have convinced themselves that there are no innocents – after all, children will grow up and some of them could be soldiers or policemen one day.

Over the centuries, rules and laws of war have developed, but terrorists feel that they cannot possibly accept them. On the other hand, they insist that when captured they should enjoy all the rights and benefits accorded to prisoners of war, that they be humanely treated, even paid wages as prescribed by the Geneva Convention. When regular soldiers do not stick to the rules of warfare – when they kill or maim prisoners, carry out massacres, take hostages or commit crimes against civilians – they will be treated as war criminals. Terrorists, on the other hand, are firmly convinced that they are not bound by these rules.

Will governments continue to accept these principles of asymmetric warfare? There is not much room for optimism. It is unlikely that governments will be impeded in their defense by laws and norms belonging to a bygone (and more humane) age.

But is indiscriminate murder of innocents not self-defeating? Will it not lead to the isolation of the perpetrators? In this respect, too, one should not overrate the extent and effect of moral revulsion. Standards of human rights (and the value of human lives) are not the same in all societies.

Sometimes there will be an outcry, as in the case of the two French journalists held hostage; the pope and the U.N. secretary-general will appeal, as well as many others. But who outside Nepal protested when 12 poor Nepalese workers were murdered in Iraq last week?

Our contemporary terrorists are neither diplomats nor experts in public relations; they know that they have and will retain, whatever they do, a certain amount of support within their own communities, and more they do not need. They do not feel restraints – except perhaps political expediency. And thus the descent to barbarism continues.