The relationship of ideas and practices

Of the different types of law taught at universities or practised in governments, commercial companies, or law firms, international law has always been the most open to moral or philosophical reflection. To engage in international law has been to involve oneself in contested ideas about legitimate government, justified forms of violence, universal rights and the direction of human progress. Ideas about the politically just and unjust are condensed in technical international law rules and institutions, giving them sharpness and actuality that has fed back as experience to the worlds of politics and thought. For example, occupation of territory, the movement of military forces or the rights of aliens are seldom discussed in fully abstract terms – without thinking of this occupation, that war, those people. Abstract legal debate and political engagement are almost always two sides of the same coin. Which is why themes such as ‘sovereignty’, ‘just war’ and the ‘right to trade and extract resources’ may be equally at home in philosophy departments, international courts, foreign ministries and political rallies. As a vocabulary and a practice, international law is deeply embedded in the creation of a global, economically and technologically driven culture. Leading ideas such as the ‘universal’ or the ‘humanitarian’ are used both to legitimise current developments and to challenge them. There are few international controversies where both sides would not regularly invoke international law in their favour.