Last week actress and UN Special Envoy Angelina Jolie joined British Foreign Secretary William Hague, non-governmental organizations, survivors, faith leaders,and international organizations for the largest ever Global Summit to End Sexual Violence in Conflict.

“It has nothing to do with sex, (but) everything to do with power,” Jolie said as she called for the international community to end the weapon of war known as rape, adding that that the perpetrators feel above the law as they are rarely charged. “We must send a message around the world that the shame is on the aggressor.”

It was Jolie's 2011 directorial debut "In the Land of Blood and Honey," a traumatic love story set during the Bosnian War two decades ago, that helped make Hague aware of the extent of sexual assault and rape in war zones.

“I have been terribly worried for months before the film came out just to get it right, it is so sensitive and important,” Jolie told FOX411 at the time, noting that she made the movie to channel her own frustrations with the international community’s failure to intervene in conflicts in a timely and effective manner. “These themes are universal, we need to understand that there are places bubbling up that we need to prevent – we need to reflect on the past and understand what we have learned.”

According to Syracuse University media professor Robert Thompson, when Jolie takes on a cause, people pay attention in ways they perhaps otherwise would not.

“Hollywood is an abstraction, a metaphor for the entertainment industry. Arnold Schwarzenegger, Fred Thompson, Ronald Reagan; the job description to being a successful entertainer has a lot of crossover with people in politics,” he said. “Angelina has managed to get more people to think about this particular issue, (beyond) the otherwise very small percentage paying attention to it before.”

It was in 2001 while in Cambodia that Jolie first became of the rapes experienced by those in war-torn countries. Since then she has visited more than 30 nations in her quest for legislation to do more to assist refugees in hostile regions. Despite the actress’s 13-year campaign, however, it wasn’t until 2008 that the United Nations Security Council officially acknowledged that rape is as an apparatus of war.

At the summit, Jolie challenged nations to work together to secure justice for survivors of sexual violence and pursue perpetrators. The United Nations also vowed to take stronger action and called for long term and in-depth solutions.

Of course celebrities can also do more harm than good when it comes to the causes they champion.

"Celebrities speaking out on issues like rape in war zones can sometimes be counter-productive," said Mylee Yc, a 12-year United States Army veteran. "It can deflect the problem; make people feel like things are being done about it when they are not."

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