German-Dutch economic relations have been so intense since the late nineteenth century that their economies have often been regarded as being mutually dependent. Although protectionism and monetary problems undermined these contacts during the interwar period, this mutual dependency has remained largely intact. The question of the relevance of this economic interdependence has been widely debated. The main protagonists in this field of discussion were, on the one hand the Liberals and on the other the (neo-)Realists. According to the Liberals, intense economic contacts guarantee political security and peace. In this they adhered to the ideas of the eighteenth century philosopher Immanuel Kant, who, in his Zum ewigen Frieden – Perpetual Peace – stated that: „The spirit of commerce, which is incompatible with war, sooner or later gains the upper hand in every state. As the power of money is perhaps the most dependable of all the powers (means) included under the state power, states see themselves forced, without any moral urge, to promote honourable peace and by mediation to prevent war wherever it threatens to break out. They do so exactly as if they stood in perpetual alliances, for great offensive alliances are in the nature of the case rare and even often less breaks out‟. Not only did Kant state that economic interdependence would ensure peace, he also believed that democracy would do so. According to Kant, merchants can influence politics and if politicians were to listen to them, peace could be achieved. After all, merchants are primarily concerned with business, and war is harmful to trade. If two countries in which the people have something to say are economically dependent on one another, this mutual dependence could lead to peaceful relations and to a desire to treat one another with respect and consideration. In De l‟esprit des Lois – The Spirit of the Laws (1758) – Charles de Montesquieu stated something similar: „The natural effect of trade is to bring about peace. Two nations which trade together, ...