– Repealing a 21-year-old rule, defense secretary Ash Carter announced Thursday that all military combat positions will now be open to women, the New York Times reports. According to CNN, that includes about 220,000 jobs in reconnaissance, infantry, and more that had previously been open only to men. "Women will now be able to contribute to our mission in ways they could not before," Carter says. "They'll be able to drive tanks, give orders, lead infantry soldiers into combat." While the previous restrictions kept women from moving up the ranks as quickly as male counterparts, they often found themselves in combat in Afghanistan and Iraq anyway, the Times reports. “It’s a thrilling day for women serving in the military—and for women across the country,” the co-president of the National Women's Law Center says. Politico reports the Marine Corps was against the move, pointing to an internal study that "suggested" combat units that included women weren't as effective as entirely male units. But a Marine Corps study also found morale in integrated units was equal to all-male units, and sexual assault levels were no higher than in the Marines as a whole, according to the Times. Carter says a 50-50 gender split in combat roles is unlikely, as only a small number of women so far have met the "high physical standards" for certain units, CNN reports. He also says integration will not come at the "cost of combat effectiveness." "The military has long prided itself on being a meritocracy," Carter says.