Bleg: When Did Male Friendship [in America] Lose Its Warmth?

I'm moving this to the head of the queue because it's relevant to a post Tyler Cowen has just posted containing travel notes about Scandanavian culture. There's a remark in the notes about sleeping habits. Originally posted in September 2011.

Over at Arcade Gregory Jusdanis has a most interesting post: From Ishmael to Joey and Ross: Whither American Manhood. It’s about how, in the past, American men expressed affection for one another quite freely—no homo!—but do not do so anymore. 
He recounts an episode from Friends where Joey and Ross somehow become inadvertent snugglers. They like it, but the community disapproves. Ewww! He contrasts that with an incident from Moby Dick in which we see Ishmael and Queequeg sharing a bed, without sex, as though it were the most natural thing in the world. Which, apparently, it was:

Although most American men of the nineteenth century would not have described this occurrence as a marriage, they would have been used to sleeping with other men. Boys became accustomed to sharing beds with their brothers and then with their roommates in college, and with strangers when traveling. So did soldiers. Physical intimacy between men was economically enforced and privacy not available. And before central heating the male body lying next to you was a literal source of warmth. Men, in short, were familiar with the smell and touch of other men.

As we know, in the nineteenth and eighteenth centuries men (as well as women) formed romantic friendships, modes of relationship that allowed much emotional, if not, physical intimacy. The letters and diaries from the Civil War, for instance, reveal men talking to each and about each other with much sweetness and warmth. This was true in earlier decades. The language of affection used by men to write to one another during the American Revolution would put it today in the realm of gay discourse.

So, what happened, Jusdanis wants to know, between then and now? When did touch become forbidden as a means of expressing affection between men?
 He makes this observation:

Although a host of factors have come into play, two developments rise above all else: the idealization of romantic marriage as the center of men’s emotional lives and the association of male-male intimacy with homosexuality. So what seemed natural before has become unnatural.

Seems reasonable to me, though I don’t know quite what to make of these factors. 
On the second, once homosexuality was out of the closet to the point where one could see gay couples publicly holding hands, embracing, and kissing, THAT changes the PUBLIC valence of male-male touching. When homosexuality was hidden, male-male touch would be just that, male-male touch. But once gay men began touching one another in public, things changed. Now male-male touching might as easily mean GAY as meaning WE’RE FRIENDS, and we wouldn’t want that, would we? 
That story does have a certain logic. But do I believe it? How should I know? I just made it up. 
On the first development, the idealization of romantic marriage, that’s a funny one. Yes, it HAS happened—but when? But what effect has it had on how men interact with women, with the women they date and the women they marry? The tricky thing about sex is that, while it DOES require close physical touching, that touching need not be an expression of affection or tenderness. Is the modern man more comfortable with and more capable of showing simple affection toward women, whether on a casual date, during serious courtship, or in marriage? I’d guess not, but I’m not at all familiar with the relevant literature. 
What I’m suggesting is that this idealization of romantic marriage is just that, an idealization, akin to Dante’s idealization of his beloved Beatrice. It has little force in the physical interaction between men and women. Or perhaps it’s a substitute for physical affection. I don’t know. Again, I’m just making this up. 
And, while I’m making things up, let’s go for a real stretcher: Does this have anything to do with the changes that restricted cartoons to kids AFTER WWII and that gutted the comics industry with restrictive codes? (I told you it was a stretcher.) What also happened after WWII, in the 1950s, is the family-oriented sit-com, Ozzie and Harriet, Father Knows Best, Leave it to Beaver, etc. That idealized, not romantic marriage (which it presupposed), but the family-with-children. I can vaguely see how these two things fit together, the cartoon ghetto and the idealized kid-centric family, but what has that to do with male-male affection? In this idealized family, does daddy get physical affection from his children? 
I don’t know. I do not know. But what I’m wondering is whether or not the phenomenon that Jusdanis has put under scrutiny—male/male friendship—is an aspect of a society-wide readjustment and restructuring of personal relationships. His remarks about homosexuality and the idealized marriage suggest as much. 
But, as I say, I don’t know. I do know, however, that things are different elsewhere in the world, such as India, and that Jusdanis isn’t the only one who’s concerned about male-male friendship. 
But, still and all: When did this happen in America? There's a long stretch between Moby Dick and Friends. It's not the sort of thing that happens over night. It happens gradually, though perhaps there's a scalled tipping point when consolidation takes place. Was there a tipping point for this phenomenon? If so, when?
ADDENDUM: I just had a jivometric mind jolt (aka brainstorm). Don't know what it means, but take a look at this graph showing the shift in men's occupations during the 20th century.

I'm wondering if this shift in affection 'tracks' the precipitous decline in primary occupations (involving work with your hands and often intense physical labor) and the simultaneous steep rise of tertiary occupations (all mental labor). From the description accompanying the graph:

The long-term shift from digging, riveting, and hammering to filling out forms, negotiating agreements, and writing software continued unabated. Even in straightforward industrial production, computerization expanded the need for administrative activities while minimizing the demand for physical labor. Blue-collar workers were increasingly found at desks rather than workbenches.