<P> The union lost roughly half of its members in the early 1930s . While the passage of the Davis--Bacon Act required payment of the prevailing wage on federal construction projects, the desperate shortage of work allowed some employers to force their employees to pay kickbacks to them to hold on to their jobs . A number of union members hopped freight cars to go in search for work . At the same time the union's old enemy, the Carpenters union, resumed its jurisdictional war with it . </P> <P> Conditions improved somewhat with the advent of the New Deal and the Roosevelt administration's creation of the Works Progress Administration, a public works project that employed thousands of iron workers and other construction workers . The union was also spurred to organize, particularly in the inside fabricating shops, by the threat of competition from the newly created Congress of Industrial Organizations . The union's membership grew slowly, reaching 40,000 by 1940 . </P> <P> The union grew even more rapidly during World War II and the years afterward, reaching 100,000 members by 1948, when John H. Lyons succeeded Morrin as president of the union . His son, John H. Lyons, Jr., succeeded him in 1961 . </P> <P> The Taft - Hartley Act, passed in 1947, limited construction unions' rights to picket worksites at which non-union contractors were working by barring secondary boycotts . Even with those restrictions, however, the Iron Workers continued to grow in the expansive economy of the 1950s . </P>

International association of bridge structural ornamental and reinforcing iron workers constitution