Whose idea was that?

A lot of the commentary after Paul Ehrlich's death said that his ideas were popular among liberals and/or "elites."  For example, Nicholas Eberstadt writes:  "In retrospect, what may look most amazing about Ehrlich’s career is the company he managed to keep. Despite his harsh and jarring rhetoric, his strident ideology, and his proclivity for veering off toward pseudo-science, Ehrlich was embraced into the bosom of the American academy. .... But perhaps this shouldn’t surprise at all. Though polemical and extreme in so many of his formulations, Ehrlich’s pronouncements on the human condition were largely in consonance with the moral panic about the 'population explosion' that swept through the American Establishment during the Cold War era."* But the New York Times obituary mentioned a detail that suggests a different possibility--Ehrlich was a frequent guest on Johnny Carson's Tonight Show.  So maybe his ideas were popular among the sort of people who watched the Tonight Show:  that is, a broad range of people.  

In 1974, a Gallup Poll asked "SOME PEOPLE FEEL THAT THE WORLD WILL REACH THE POINT SOMEDAY WHERE, BECAUSE OF POPULATION AND ECONOMIC GROWTH, THERE WON'T BE ENOUGH WATER, LAND, FOOD, AND OTHER NATURAL RESOURCES FOR EVERYBODY. OTHER PEOPLE BELIEVE THAT THE WORLD CAN CONTINUE TO GROW WITHOUT RUNNING INTO SERIOUS SHORTAGES BECAUSE SOMEBODY WILL ALWAYS BE ABLE TO SOLVE THESE PROBLEMS. DO YOU, YOURSELF, FEEL THAT SOONER OR LATER WORLD POPULATION AND ECONOMIC GROWTH WILL HAVE TO BE REGULATED TO AVOID SERIOUS SHORTAGES, OR NOT?"  62% said yes and 30% said no.  It was asked again in 1976:   65% said yes and 27% said no.  

Using the 1976 survey, here are "yes" answers by self-rated ideology 

Very liberal                                54%                
Moderately liberal                     76%
Middle of the road                     74%

Moderately conservative            66%
Very conservative                       58%
Don't know                                 70%

Support seems to have been somewhat higher in the middle (and those who didn't choose a label) and lower in the extremes.  Why wasn't there a straightforward relationship?  I think it's because there were two offsetting factors:  on the one hand, environmentalism was associated with concern about overpopulation; on the other hand, the Malthusian position suggested that trying to help poor people would be futile or harmful, giving it an affinity with conservatism, 

Not college graduate                      67%

College graduate                            79%

College graduates were more likely to think that regulation would be necessary.  But if we restrict it to whites:

Not college graduate                      73%

College graduate                            80%

The difference by education is smaller (and not statistically significant).  The reason that restricting it to whites makes a difference is that blacks were much less likely to think that regulation would be necessary (divided about 50/50) and less likely to be college graduates.  I considered a few other group differences:  men and younger people were a bit more likely to agree, and there were no clear differences by religion.  I'm not sure why race was so important--I just tried it because it's a standard control variable.  But the general point is that it wasn't just the "Establishment": most people were concerned about the "population explosion," to the point of supporting a policy that would now be regarded as pretty extreme. That's not hard to understand:  world population was growing rapidly, and people often think in terms of a fixed stock of resources.  

*As a sociologist, I have to note that this is an example of the dumbing down of the term "moral panic" to  be just a way of dismissing something as not a real problem.  In the original sense, the "moral" part was important.  

[Data from the Roper Center for Public Opinion Research]