Women are women when they reach puberty, men need to prove they are men every single day of their adult lives. The professional name for this is precarious manhood.
Legally men have certain responsibilities women don't have. Men by law must protect women, yes that is the law, if the man is nearby and a woman is in danger. Constant fear is a part of being a woman, but also part of her sexuality. A little fear brings sexual arousal, as long as this fear is not an actual threat, similar to scary rides for children. Fear is also part of a woman's makeup, thus they take fewer risks and thus earn less than men. This fear is also part of living longer, men take risks and die, in fact they have been required to under threat of being executed, in many countries this is still the case with conscription, think Korea and Singapore. In reality though, men are subject to more acts of violence than women. Even criminals will shy away from attacking women and children, and in prison they will treat perps who do this harshly.