But the higher costs of producing coal also led coal companies to substitute machinery for labor, reducing the number of miners.
By the 1960s, many coal-mining towns were almost ghost towns. But few people connect the dots to the glory years of John L. Lewis.
The United Mine Workers did not kill the goose that laid the golden eggs, but it created a situation where fewer of those golden eggs reached the miners.
It was much the same in the automobile and steel industries, where large pensions and costly work rules drove up the price of finished products and drove down the number of jobs.
There is a reason why there was a major decline in the proportion of private-sector employees who joined unions.
It was not just the number of union workers who ended up losing their jobs. Other workers saw the handwriting on the wall and refused to join unions.
There is also a reason why labor unions are flourishing among people who work for government.
No matter how much public-sector unions drive up costs, government agencies do not go out of business. They simply go back to the taxpayers for more money.
Consumers in the private sector have the option of buying products and services from competing, non-union companies - from Toyota instead of General Motors, for example, even though most Toyotas sold in America are made in America.
Consumers of other products can buy things made in non-union factories overseas.
But government agencies are monopolies. You cannot get your Social Security checks from anywhere except the Social Security Administration or your driver's license from anywhere but the DMV.
Is it surprising that government employees have seen their pay go up, even during the downturn, and their pensions rise to levels undreamed of in the private sector?
None of this will kill the goose that lays the golden egg, so long as there are both current taxpayers and future taxpayers to pay off debts passed on to them.
Sowell is a senior fellow at the Hoover Institution at Stanford University in California. His website is www.tsowell.com.