what gives men the power to impose social manhood pressures on each other?

Why does it create so much pressure if any tom dick harry, but especially your peers or friends question your sexual interest in girls.

What gives their remark, so much power?

It is not that they have inherent power, and that’s make their remark so powerful, that you have no option but to submit to what they have said (and pursue girls in an apparent manner!). Well they do have power, that they get from falling in line with the social pressures. But what makes their remark doubly powerful is the fact that the pressure has already been created by the society. All they are doing is throwing the pressures at you.

So, we have to ask men to stop throwing the pressures at each other, in order to strengthen men's spaces and empower men.