Among the evidence ignored by Obama, Carter and others are the results of a nine-month field test by University of Pittsburgh researchers who found that all-male USMC units outperformed mixed-gender units in 93 out of 134 ground combat tasks (69 percent).

This observation is no criticism of military women, who are just as determined, courageous and committed as their male counterparts. But contrary to what our government seems to think, the requirements of combat can’t be compromised to meet social goals of gender equality.

Likewise, proud assertions that allowing women in combat is yet another advance for equality akin to racial integration and acceptance of gays is nonsense. Gay men and black men are still men — and the vast majority of women in close combat will never be their equal.

Because of physical differences, including the fact that men have 40 percent more upper body muscle mass, women are at a disadvantage in combat, which often requires long deployments of deprivation and hardship, including toting 60 to 100 pounds of equipment.