A scientific tradition from the Soviet Union offers a good example:
The biological inheritance of acquired characteristics
was an official Communist dogma for decades.
This system of belief was required by the party in power
because it fit so well with their social theories of human progress.
They wanted to believe that behavioral improvements in human beings
could be passed on to the next generation in their genes.
Of course, biologically, this is utter nonsense:
Whatever behaviors we develop during our lives,
no matter how well established,
will not change the genes we pass on to the next generation.
But this politically-motivated dogma
prevented progress in Soviet biology for decades.

     Lest we become complacent that such distortions of truth
could never happen in the West, three examples will now be offered
illustrating how science as presented in the mass media
led to false conclusions in the popular mind.

     Toxic shock syndrome was in the news for just a few months.
And it led to the withdrawal of one kind of tampon from the market.
However, the cause of this syndrome
was not tampon design but tampon misuse.
Women who left large tampons in place for days,
sometimes caused infections that spread thru-out their bodies.
Ideological conformity led by media vilification of just one manufacturer
led to the wide-spread belief that those tampons were defective.

     Silicon gel breast implants had a similar history.
Because a certain percentages of them leaked or broke,
women with such implants
began to blame a wide variety of health problems
on these foreign objects in their bodies.
But objective scientific research determined
that silicone gel is an inert, non-toxic substance,
which was the reason it was selected in the first place.
However, this was not established until after
several women had already won lawsuits
based on the theory that they had been harmed
by leaky silicon gel breast implants.
And the major manufacturer went bankrupt as a result of this bad science.

     Gulf War Syndrome was a similar phenomenon,
this time mostly for men.
The United States engaged in a war against Iraq in 1990 to liberate Kuwait.
For years afterwards, soldiers who had served in the Gulf
complained of a variety of health problems
for which no specific cause could be found by scientific investigation.
Many theories were advanced and the media convinced the public
that Gulf War Syndrome was real enough
for the Congress to pass special compensation
for service men and women who had the undiagnosable problems.
But then scientific investigation showed that
service people who had not served in the Persian Gulf
had the same rate of undiagnosable health problems.
This was not reported nearly as fully as the original speculations,
so the majority of Americans who remember the Gulf War
still believe there was a Gulf War Syndrome.

     The Vietnam War illustrates another mistake of conformist thinking.
In the 1960s and early 1970s,
the United States supported one side in the
civil war between two parts of Vietnam.
The political thinking behind this policy
was that one side was capitalist and the other Communist.
And if the United States allowed the Communist side to win,
they would soon take over the rest of southeast Asia,
which would be the first step toward world domination by Communism.

     History since 1975, when the U.S. withdrew from Vietnam,
has shown this prediction to be completely groundless.
The new Vietnam—while still controlled by a central government—
has become more successful in commerce than many of its neighbors.
And 45 years later, still no dominoes have fallen.
There is no sign of a blood-bath.
The killing stopped soon after the U.S. withdrew in 1975.

     In this example of conformist thinking,
the American people were divided, even during the war in Vietnam.
Anti-Communism was the official government ideology of the United States.
But a significant and vocal minority of the American people
wanted to end the war by withdrawing
—which is what eventually did happen.

    Open discussion and vigorous dissent eventually did change
American political and military policy with regard to Vietnam.
Reason did eventually prevail
against the established forces of ideological conformity.
And the longest and most foolish war ever fought by the United States
was brought to an end by the withdrawal of all foreign military forces.
It will probably be seen by history as the last anti-Communist war.
And let us hope that it will be the last example
of how destructive ideological conformity can become.