However little sympathy might be felt with the various projects for the military or economic aggrandizement of France on the Left Bank, there was one French argument that was unanswerable: the Left Bank and the Rhine must not be made the basis of a new attack against France and thus against the world’s peace. Here Prussian militarism had used its opportunities to the full. The Rhine valley was covered with munition factories, with forts and garrisons and parade grounds, with bridges and strategic railroads, furnished with long detraining platforms in the open country or great camps like Elsenborn on the Belgian frontier. And the campaign of 1914 had shown to what use all this could be put in sudden attack. “Not another German soldier on the Rhine,” was a common form of the French demand. The demilitarization of the Left Bank was an elementary demand of national, and international, security. The clauses to this effect in the treaty are brief but full of meaning: Article 42. Germany is forbidden to maintain or construct any fortifications either on the left bank of the Rhine or on the right bank to the west of a line drawn 50 kilometres to the East of the Rhine. Article 43. In the area defined above the maintenance and the assembly of armed forces, either permanently or temporarily, and military manoeuvres of any kind, as well as the upkeep of all permanent works for mobilization, are in the same way forbidden. Article 44. In case Germany violates in any manner whatever the provisions of Articles 42 and 43, she shall be regarded as committing a hostile act against the Powers signatory of the present Treaty and as calculated to disturb the peace of the world.