When America’s powerful labor union movement reached its peak in the mid-1960s, embracing almost half of the active U.S. workforce at that time, it seemed that organized labor was here to stay and grow.

Much of this was due to the imposition of union shops in the manufacturing industry, especially during that sector’s heyday in the post-World War II period. This made it mandatory that all employees hired also would have to become union members. This was reinforced by such powerful titans as John L. Lewis, founder of the Congress of Industrial Organizations and Harry Bridges, the charismatic head of the Longshoreman workers’ group, who controlled the total labor force employed in all import/export U.S. trade activities.