Final answer:
The proportion of U.S. workers belonging to unions has declined due to shifts in the economy, global competition, and a changing legal landscape.
Step-by-step explanation:
The proportion of U.S. workers belonging to unions has declined dramatically since the early 1950s. This can be attributed to various factors:
- The shift from manufacturing to service industries, which have lower unionization rates.
- The force of globalization and increased competition from foreign producers, leading to a decline in jobs in traditionally unionized industries.
- A reduced desire for unions due to workplace protection laws that now exist, which provide some of the benefits traditionally fought for by unions.
In summary, the change in unions over the past 50 years can be attributed to shifts in the economy, increased global competition, and a changing legal landscape.