 Given that Germany had engaged in covert rearmament with the co-operation of the Soviet Union starting in 1921 (a fact that had become public knowledge in 1926) and that every German government had gone out of its way to insist on the moral invalidity of Versailles, claiming it was based upon the so-called "Kriegsschuldlüge" ("War guilt lie") that Germany started the war in 1914, the French had little faith that the Germans would willingly allow the Rhineland's demilitarised status to continue forever, and believed that at some time in the future Germany would rearm in violation of Versailles, reintroduce conscription and remilitarise the Rhineland.The decision to build the Maginot Line in 1929 was a tacit French admission that without the Rhineland as collateral Germany was soon going to rearm, and that the terms of Part V had a limited lifespan.After 1918, the German economy was twice as large as that of France; Germany had a population of 70 million compared to France's 40 million and the French economy was hobbled by the need to reconstruct the enormous damage of World War I, while German territory had seen little fighting.