DCP probably exchanged texts like these asking young men about masturbation

[huckelberry]

Well there were presidents.

Yes there were. . . 46 of them, to be exact. . . But what do they have to do with masturbation?

Ouch, correction made, do I have to stand in the corner for long?

[huckelberry]

Here are parts of article with more historical perspective.
https://www.encyclopedia.com/internatio ... sturbation

Within Christianity masturbation, which was largely believed to be particularly the vice of the celibate and the young, was included under the heading of sins of the flesh and considered to contravene natural law. However, it was not the subject of particular scrutiny in the confessional, and unlike other sins of the flesh (such as sodomy), it was not penalized under secular law within Christendom.
For many centuries the Western medical tradition considered it to be no more deleterious than any other manifestation of lust—that is, if not indulged to excess. Indeed, within the Galenic humoral system of medicine, excessive continence causing retention of semen was regarded as almost equally damaging.
THE INVENTION OF A MENACE

These attitudes changed some time around the first decade of the eighteenth century, for reasons that are still the subject of considerable historiographical debate. The immediate cause is well known. Sometime during the first two decades of the century an anonymous volume entitled Onania: or, The Heinous Sin of Self-Pollution, and All its Frightful Consequences, inBoth Sexes, Consider'd, with Spiritual and Physical Advice to those, Who Have Already Injur'd Themselves by This Abominable Practice. And Seasonable Admonition to the Youth of the Nation, (of both Sexes) and Those Whose Tuition They Are Under, Whether Parents, Guardians, Masters, or Mistresses was published in London. Its pathbreaking message about the uniquely disastrous consequences of the solitary vice was disseminated throughout Europe. Its claims for the physical deleteriousness of masturbation seem the stranger, given that the anonymous author—possibly a Dr. Bekkers, an obscure figure—appears in fact not to have been a doctor but a clergyman, or at least at one time in orders. Certainly he gave more attention to the sinfulness of the practice than its harmfulness, even while proffering a patent quack remedy. The work probably deserves a place in the history of advertising as an early example of creating anxiety about an alleged affliction while holding out a remedy for it. At this stage, masturbation, besides having terrible spiritual consequences, was presented as the cause of a plethora of physical (rather than mental) ailments, affecting not only the genitals themselves (with stranguries, or the slow and painful emission of urine; priapism, a painful persistent state of erection; impotence; and discharges) but the entire bodily system (with epilepsy, consumption, fainting fits), and causing infertility in both sexes.

The book went into many editions. Letters purportedly from grateful readers (and replies) were published in the later editions. Its actual impact is hard to gauge, but at the very least it was presumably profitable enough to be kept in print promoting the advertised medicines. It was very much part of a subculture of quackery and did not figure in serious medical discourse, although there were a number of imitations as well as counterattacks. In 1724, Bernard de Mandeville, in A Modest Defence of Publick Stews (i.e., public brothels), perhaps a satire on the onanism panic, argued that fornication with prostitutes was preferable to masturbation.

.....

T

Tissot constructed a respectable theory on the cause of the disease of masturbation by careful and selective citation from texts of the ancients and Renaissance physicians about the evils of excessive lust in general. The effects he described were pervasive, afflicting the digestive, respiratory, and nervous systems, creating debility and pallor, and affecting the faculties and memory. In women it caused hysteria and a plethora of uterine problems. Unlike the anonymous author of Onania, Tissot produced physiologically based arguments consonant with current medical theories for the reasons why masturbation had such evil consequences. On the one hand he drew on humoral theory for an explanatory model, making the suggestion (which became an enduring tradition) that the loss of one ounce of seminal fluid was equivalent to losing forty ounces of blood. On the other he proposed that the activity was a damaging expenditure of nervous energy in an artificially caused convulsive spasm, upsetting the natural balance of the bodily mechanism. He did not propose any patent remedy for the affliction, preferring to make recommendations for a regimen, such as cold baths, a healthy life-style, exercise, regularity of the bowels, moderate amounts of sleep, and an endeavor to keep one's thoughts pure. However, quinine, iron water, and other strengthening medicines were also mentioned.

Masturbation became universally reprobated in Europe. There seems to have been little difference in response between Catholic and Protestant cultures, although there were local variations. The question that fascinates the historian is why, at this particular juncture, a previously largely ignored sexual practice came to be seen as the root of a massive amount of physical harm. It has been argued that the new view of masturbation provided an explanation for a variety of bodily ills that existing medical science was ill equipped to account for, at a time when an increasingly rationalist climate of thought was rejecting supernatural causality. But this argument does not account for the staying power of the belief in masturbation's ill effects; that belief persisted well beyond the rise of alternative explanations for many of the diseases attributed to the practice, although the catalog of its alleged consequences often altered.



.....
The relationship between masturbation and what might seem a far more pressing cause of concern regarding sexual conduct, venereal diseases of epidemic prevalence, is convoluted. Many of the symptoms attributed to masturbation—genital discharges, lassitude and debility, sores, rashes and spots, uterine disorders—could well have been those of syphilis, gonorrhea, or a range of other unidentified venereal afflictions. Alternatively, perhaps the prevalence of venereal diseases led some individuals to take the logical step of resorting to masturbation as a substitute for potentially dangerous copulation for the relief of sexual desire. Yet for well over a century promiscuous intercourse (at least for men) was seen as a lesser danger than masturbation, and resort to prostitutes was sometimes recommended as a "cure."

....


One of the works most influential on the perception of masturbation throughout Europe in the nineteenth century was Claude-François Lallemand's three-volume Des pertes seminales involuntaires (On involuntary seminal discharges; 1842). He was more concerned with the pathological loss of semen—"spermatorrhoea"—through involuntary causes, which could be brought about through the irritation of the genital organs set up by habitual masturbation. "Spermatorrhoea" was seen as being at least as deleterious as masturbation, with the additional horror that it could not be terminated by exercising willpower and self-discipline. It was a godsend to quacks. The imprimatur of Lallemand's name gave it credence within the medical profession, but doctors were careful to differentiate themselves from "advertising quacks" and their often spurious diagnoses of this complaint.

By the last quarter or so of the nineteenth century a few physicians in several European countries were beginning to question the role ascribed to masturbation in the etiology of so many disorders, and some even pronounced it harmless. Sir James Paget, in Britain, suggested during the 1870s that, although a filthy and unmanly habit, it was no more deleterious than sexual intercourse. Like intercourse, it could be debilitating in excess, and because no partner was needed, it was easier to pursue it recklessly.
THERAPEUTICS AND GENDER ATTITUDES

..
During the later decades of the nineteenth century a new campaign against the dangers of self-abuse was mounted. Largely directed against the adolescent boy, and initially focusing on the upper and middle classes, it was fed by anxieties about national fitness and the capacity of the existing elite to continue to rule in the face of challenges from rival nations and rising social groups within the nation. The constant subtext of venereal disease, in a period during which clinical observation and investigation were increasingly revealing the long-term and congenital effects of syphilis, was also a factor.

While similar manifestations occurred in other European countries, possibly the most coherent form of this new mutation of masturbation panic can be seen in the "social purity" movement that arose in Great Britain. This movement represented an alliance between feminists who had fought against the regulation of prostitution under the Contagious Diseases Acts of the 1860s, religious interests (provincial non-conformists in particular), public health advocates (medical and nonmedical), and educators.


.........

vast amount of literature was produced by the social purity movement. In addition to books such as the age-graded works of the American clergyman Sylvanus Stall in his "Self and Sex" series, What a Young Boy [or Young Man, Young Husband, Man of Forty-Five] Ought to Know (1897–1907), widely disseminated in Europe, a plethora of pamphlets was produced both by individuals and a range of organizations, distributed free or at a cost of a few pence. These pamphlets found probably their largest outlet in the various youth organizations being established to cope with the newly defined problem of adolescence.
SEXOLOGY AND PSYCHOLOGY

Toward the end of the nineteenth century, a new science of sexology endeavored to investigate sexual behavior, initially in its more anomalous manifestations. Richard von Krafft-Ebing, the Austrian psychiatrist and forensic medicine expert, noted "onanism" as well as degenerate heredity in many cases in his encyclopedic compilation of sexual deviations, Psychopathia sexualis, first published in 1886 and subsequently in much expanded editions. However, other writers, notably the British doctor and man of letters Havelock Ellis, drew on anthropological and animal studies to suggest that "auto-erotism" was an almost universal practice. Far from being a uniquely human vice, many animals resorted to analogous behavior, and it was found even among the "primitive" races, contradicting the notion that it was a malign by-product of civilization.

Gradually a somewhat more humane attitude to masturbation emerged. If it was still regarded as reprehensible and not to be encouraged, the horror-mongering of earlier epochs, it was argued, had done much to cause the neurotic sufferings attributed to the practice itself. This new view, however, took quite some time to influence general opinions on the matter. Sir Robert Baden-Powell's Scouting for Boys (1908) and Rovering to Success (1922) threatened dire outcomes if "beastliness" was practiced, and these texts were published with relevant passages unchanged until well after the Second World War. Leading childcare manuals of the interwar period advised tying children's hands at bedtime to prevent them from masturbating, even as the idea of gently distracting the child's attention, as opposed to threats and punishment, was creeping in as the best mode of handling the "problem." The most progressive works even came to define it as a natural stage in childhood and adolescent development (though "neurotic" in adults).
........

[huckelberry]

"According to historian George Lincoln Burr, "the Salem witchcraft was the rock on which the theocracy shattered."

This interesting observation is in Wikipedia article of salem witchcraft trials. I had looked at that after my mind made a casual note about the time sequence between European witch hysteria drawing to a close and the growth of this new social concern. (danger of masturbation) It is not an immediate switch but close. (people may seize upon a target to project fear of social disorder, or is it simpler fear?)

///quoting from my overly long quote above:

masturbation became universally reprobated in Europe. There seems to have been little difference in response between Catholic and Protestant cultures, although there were local variations. The question that fascinates the historian is why, at this particular juncture, a previously largely ignored sexual practice came to be seen as the root of a massive amount of physical harm. It has been argued that the new view of masturbation provided an explanation for a variety of bodily ills that existing medical science was ill equipped to account for, at a time when an increasingly rationalist climate of thought was rejecting supernatural causality. But this argument does not account for the staying power of the belief in masturbation's ill effects; that belief persisted well beyond the rise of alternative explanations for many of the diseases attributed to the practice, although the catalog of its alleged consequences often altered.