Why is it that women are always singled out when it comes to “women’s issues,” while men are rarely singled out when it comes to “men’s issues”?

For example, since women experience sexual assault far more often than men, campaigns and initiatives are typically framed as “Stop sexual violence against women and girls.” Similarly, if Black women were being killed at the same rates as Black men, the movement would be called “Black women’s lives matter.” Instead, because the majority of Black people being killed are men, the focus is on “Black lives matter,” not “Black men’s lives matter."
Why is it that women are always singled out when it comes to “women’s issues,” while men are rarely singled out when it comes to “men’s issues”?
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