Men and non-men

The entire question about segregating males between two categories has been of who's a man, and who's not.

The earlier, most basic distinction was based on natural gender.

The males who innately felt to be females, were classified as 'third gender' and not 'men'.

The others were 'men'.

Then the distinction shifted from natural gender to what was socially defined as the roles of men and third gender.

This role hinged on being the penetrator or the penetrated. It was (wrongly) held that the it is the female role to be penetrated, and hence only the third gender were allowed that, and it was extremely stigmatized for men. The situation continued for more than two thousand years, and this distinction between men is practised till today in all non-western socities -- which don't divide males on the basis of homo-hetero, but on the basis of active and passive. The active is 'man' or 'straight', and the passive is 'third gender' or 'gay'.

In the west, the roles of men and third gender were further misdefined, and men were now supposed to desire only women, while all kinds of male desire for men was thought of as effeminate and hence belonging to the 'third gender'.

Men were no defined as 'heterosexual' or 'straight' males, and the third gender were defined as 'homosexual' or 'gay' males.

However, the crux of the two categories remain as that of 'men' and 'third gender', or 'men' and 'non-men' or 'men' and 'queer', and straight or heterosexual males are widely thought of as being the real men, while gays are considered to be effeminate, queers.

It is true to a large extent, because mostly, only effeminate males take on the 'gay' identity while the masculine males don the 'straight' identity, that may not reflect their true sexuality but it reflects their masculine gender, which is more important for men.