"Not everyone is going to be able to be a combat soldier, he said. "But everyone is entitled to a chance."
Each branch of the military must supply the secretary of defense with a report, which will be presented in May, outlining how it will adapt to the lifting of the ban. The branches have until 2016 to apply to keep certain positions closed to women.
"The services will bear the responsibility for providing the thorough analysis needed to articulate what's best needed for the armed forces," Gen. Dempsey said. "We all wear the same uniform, and we all fire the same weapon."
Proponents argued that women were already serving in combat roles because the changing nature of warfare made traditional battle lines obsolete. No longer could women hide behind an arbitrary line.
Opponents argued largely that they were opposed to having women serve in combat roles, that they worried their presence would cause the military to lower its fitness standards or that the women wouldn't have privacy working close to male soldiers.
"I did not think it would come in my lifetime," said Col. Sharon M. Johnson, who is stationed at Pope Air Field Base in North Carolina and worked for a time at the 911th Airlift Wing in Moon. "I was surprised and delighted, and I think now the hard work starts for everybody."
President Obama issued a statement Thursday saying: "This milestone reflects the courageous and patriotic services of women through more than two centuries of American history and the indispensable role of women in today's military. Many have made the ultimate sacrifice, including more than 150 who have given their lives in Iraq and Afghanistan - patriots whose sacrifices show that valor knows no gender."
Meanwhile, those who have closely monitored the changing roles that women play in the military are waiting patiently to see exactly how many new jobs open up to women.
"It's evolutionary," Francoise Bonnell, director of the U.S. Army Women's Museum. "I think it's one of those changes where in 20 years, we'll look back and say, 'Wow, it was a big change at the time, but we've learned a lot from it."
Dempsey warned that no one knows where future conflicts will be, so the military needs time to review and revise standards for combat jobs.
He suggested that eliminating the ban on women in some combat roles could help with the ongoing sexual assault and harassment problems in the military.
"When you have one part of the population that is designated as warriors and another part that's designated as something else, I think that disparity begins to establish a psychology that in some cases led to that environment." said Dempsey. "I have to believe, the more we can treat people equally, the more likely they are to treat each other equally."
This article contains information from the Associated Press.