From the 1920s Ireland had high trade barriers such as high tariffs, particularly during the Economic War with Britain in the 1930s, and a policy of import substitution. During the 1950s, 400,000 people emigrated from Ireland. It became increasingly clear that economic nationalism was unsustainable. While other European countries enjoyed fast growth, Ireland suffered economic stagnation. The policy changes were drawn together in Economic Development, an official paper published in 1958 that advocated free trade, foreign investment, and growth rather than fiscal restraint as the prime objective of economic management.