Illegal Hispanic immigration into the USA has undoubtedly brought troubles in its wake -- particularly in recent years. There is a high level of criminality in the resultant population and a high level of almost every social pathology you can name. See here and here for background. Most conservatives attribute the troubles with the illegal immigrant population to the way they have been mollycoddled and allowed to get away with anything by the American Left. If there is no pressure to be law-abiding, why should the immigrants be law-abiding? And I heartily agree with that analysis. I think it is mainstream America that has created most of the immigrant problem by bowing down to the unending demands for "tolerance" from the American Left.
"Godless" at Gene Expression, Randall Parker and others, however, believe that the problem is more deepseated than that. They believe that with the best will in the world the Hispanics would still be an underclass. They base that view on the low average IQ recorded not only among the immigrants but even among their children and grandchildren. They take that low recorded IQ to represent a permanent genetic handicap. I am broadly sympathetic to that sort of reasoning and believe that some intergroup differences are real and important and do have large explanatory value.
In my 30+ years as a psychometrician, however, I have developed a healthy awareness of what can go wrong in measuring psychological attributes, and in my own work I have always placed an unusual degree of emphasis on looking carefully at the criteria used to validate any given test or scale. And that emphasis has been greatly rewarded from an academic viewpoint in that I have on occasions been able to show a convergence between the psychometric measuring instrument and other indicators of what it purports to measure that is far greater than is normally obtained. A corollary of that, however, is that I am also unusually skeptical of a psychometric instrument that does NOT show a good convergence with other indicators of what it purports to measure.
And that is why I am skeptical of the Hispanic IQ data. It seems to me that the Asian origins of the "Hispanics" -- really Amerindians -- and their historically recent achievements in building notable civilizations without outside input (the Aztec, Toltec, Olmec and other empires) do NOT suggest an unusually disadvantaging gene pool. So if it's not their gene pool that is causing their low IQ scores, what is it?
I think that what has happened is that a poorly-educated rural population has arrived in the USA only to be thrown into a behavioral sink, the behavioural sink of America's predominantly black underclass. Because of their lack of skills, education and urban (particularly scholarly) culture the immigrants have from the beginning found only low-paid manual work and thus been forced to live very cheaply. And living cheaply has meant by and large living in predominantly black slums. And that slum environment has given their children values that are anti-intellectual, to say the least. And in his many essays on the subject Theodore Dalrymple has documented graphically how hard it is to climb out of such an environment. So the low recorded IQ of the Hispanic immigrants themselves is attributable to their rural origins (rural populations normally score badly on IQ tests) and the low recorded IQ of their children is attributable to the moronic environment in which they have grown up. Only about two thirds of IQ is genetic. The rest is cultural. And there could be few worse cultures for the development of intellect than the slums of (say) L.A.
In ideal circumstances, a home environment formed by a culture that has been obsessed with education for 2,000 years (as in the case of the East Asians) might have allowed the children to rise above that handicap, but the Hispanics do not come from such a culture. So my belief is that if the children of the Hispanics could be got into good schools and put into a good environment generally, they would eventually merge into the American mainstream. I may well be wrong but given the unlikelihood that the Hispanic population of the USA will ever decline, all Americans should hope that I am right.
(For convenience, I have combined my post above with my previous posts on immigration to make a single article. See here or here).