One of the ways of trying to reduce the vast disparities in economic success, which are common in countries around the world, is by making higher education more widely available, even for people without the money to pay for it.
This can be both a generous investment and a wise investment for a society to make. But, depending on how it is done, it can also be a foolish and even dangerous investment, as many societies around the world have learned the hard way.
When institutions of higher learning turn out highly qualified doctors, scientists, engineers and others with skills that can raise the standard of living of a whole society and make possible a better and longer life, the benefits are obvious.
What is not so obvious, but is painfully true nonetheless, is that colleges and universities can also turn out vast numbers of people with credentials, but with no marketable skills with which to fulfill their expectations. There is nothing magic about simply being in ivy-covered buildings for four years.
Statistics are often thrown around in the media, showing that people with college degrees earn higher average salaries than people without them. But such statistics lump together apples and oranges — and lemons.
A decade after graduation, people whose degrees were in a hard field like engineering earned twice as much as people whose degrees were in the ultimate soft field, education. Nor is a degree from a prestigious institution a guarantee of a big pay-off, especially not for those who failed to specialize in subjects that would give them skills valued in the real world.
But that is not even half the story. In countries around the world, people with credentials but no marketable skills have been a major source of political turmoil, social polarization and ideologically driven violence, sometimes escalating into civil war.
People with degrees in soft subjects, which impart neither skills nor a realistic understanding of the world, have been the driving forces behind many extremist movements with disastrous consequences.
These include what a noted historian called the "well-educated but underemployed" Czech young men who promoted ethnic identity politics in the 19th century, which led ultimately to historic tragedies for both Czechs and Germans in 20th century Czechoslovakia.
It was much the same story of soft-subject "educated" but unsuccessful young men who promoted pro-fascist and anti-Semitic movements in Romania in the 1930s.
The targets have been different in different countries but the basic story has been much the same. Those who cannot compete in the marketplace, despite their degrees, not only resent those who have succeeded where they have failed, but push demands for preferential treatment, in order to negate the "unfair" advantages that others have.
Similar attempts to substitute political favoritism for developing one's own skills and achievements have been common as well in India, Nigeria, Malaysia, Fiji, Sri Lanka and throughout Central Europe and Eastern Europe between the two World Wars.
Such political movements cannot promote their agendas without demonizing others, thereby polarizing whole societies. Time and again, their targets have been those who have the skills and achievements that they lack. When they achieve their ultimate success, forcing such people out of the country, as in Uganda in the 1970s or Zimbabwe more recently, the whole economy can collapse.
Against this international background, the current class warfare rhetoric in American politics and ethnic grievance ideology in our schools and colleges, can be seen as the dangerous things they are. Those who are pushing such things may be seeking nothing more than votes for themselves or some unearned group benefits at other people's expense. But they are playing with dynamite.
The semi-literate sloganizing of our own Occupy Wall Street mobs recalls the distinction that Milton Friedman often made between those who are educated and those who have simply been in schools. Generating more such people, in the name of expanding education, may serve the interests of the Obama administration but hardly the interests of America.
Thomas Sowell is a senior fellow at the Hoover Institution, Stanford University, Stanford, CA 94305. His website is www.tsowell.com.