A common criticism of this subreddit that seems to pop up at least twice a week is, in a nutshell:

"Why can't masculinists/MRAs work together with feminists to better achieve gender equality?"

and there are of course many reasons put forth because of this. The most common I have seen are:

  • Because they won't work with us/demonize men's rights advocacy as an uber-Conservative astroturf movement filled with bitter white males who want to hold onto power
  • They treat men's problems as insiginifcant and not worthy of attention
  • Many feminists are anti-male and the movement is rife with misandry
  • Feminist organizations such as NOW push forward anti-male agendas/NAFALT rhetoric
  • Many of those involved in the men's rights movement feel statistics are manipulated to suit ideological ends
  • ShitRedditSays

I'm sure there are others, and these criticisms, while all quite valid to varying degrees, often depending on context, they are not the best answers to give, and it's because the question is fallacious.

Feminism is, at its core, a set of philosophical theories rooted in a very large branch of philosophy known as postmodernism, which can be described in a nutshell as a rejection of the objective-truth model that defined modernism/rationalism. Feminism is not rooted in the notion that women are oppressed, but rather they are unilaterally oppressed in every sphere of society by virtue of the construct of being a woman, which has been constructed to be an oppressed class to serve the more powerful. Because of the perceived power structure of society that post-modernists fit into their ideology, all problems in society are rooted in its very construction as it stands now, from objective logic to the very language we use (see Écriture féminine), and by controlling the language, it constrains the discourse by acting as if any premises NOT based in postmodernism are fallacious/erroneous. It is epistemological, where there is no real 'objective' reality. This brings clarification to the meaning of the oft-heard sentiment that the solution to men's problems is more feminism: the end goal is the deconstruction of gender completely, where one's problems will not be delegated to gender, because gender will not be a concept, or more specifically, that the appearance of oppression is actually privilege over the oppressed.

Now, why is the question fallacious? Because it is false equivalence, and a few other red herring arguments . A feminist is not necessarily a woman's right advocate, and the ends are not the same. This is the great lie of feminism: that it is rooted in the benefit of women. It is not, it is, rather, the attempt to disrupt perceived power structures via the elevation of 'women' to be closer to the same social class that it perceives society to be oppressed by. Some feminists might be women's rights advocates, some (like Erin Pizzey could never be described as such. You can see this clearly in the early stages of feminism and the women's suffrage movement, which was eventually co-opted by feminist ideologues as the first feminist victory.

Now, an intellectually sound argument would be:

"Why are those fighting for women's issues and men's issues not working together?"

And there are issues As it stands, however, you are asking a deconstructionist movement to work with a constructivist/reparative one. The theories are only not the same: they're diametrically opposed. Feminism by its very nature presupposes problems by the solutions necessitated by its framework (i.e. men do not get custody because women are seen as being natural caretakers and thus oppressed, therefore the problem will be fixed by female empowerment), whereas men's rights is by and large much more akin to to ethical humanism, where problems are identified first and the solutions later worked out via utilitarianism.