MRAs will self identify and SJW is pejorative though you get people trying to "reclaim" it by self identifying.
MRAs on reddit are mostly the extreme types who reeeaaallly believe women are taking over the world and stomping on men. there's a lot of cross over with those that truly believe in shitty pickup artist types (there was that one who was saying rape is ok cause women want it and it's ok to assault a woman if you want her, he got banned from several countries it's that bad) and you might see redditors refer to them as "TRPers" or Terpers. which stands for "the red pill".
It's my everlasting hope that Snapzu disallows those types of tribes (and the women versions of them because screw that noise!) Because freedom of speech is one thing and hate speech is another.
If memory serves the term SJW came from UCLA (school) due to things like the Rodney King Riots and MRA was a response to second and third wave feminism. Both came about in the early 90's I think but then again I could be wrong.
Both terms were hijacked those who expose extreme views on the issues which is sad. MRA was originally people whom wanted to rewrite items such as alimony laws, and many moderate feminists supported them. Men's rights then became, like third wave feminism, the twisted pile of insanity it is now. Its sad that good things are often perverted by twats.
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