(CNN) -- Last night's shooting rampage at a movie theater in Aurora, Colorado, was a nightmare. Authorities have already arrested a suspect. Four weapons were recovered in the shooting scene, including a shotgun and two handguns. Twelve people have been killed, with many more injured. According to law enforcement officials, the weapons were purchased legally by the suspect in the last six months. The shooting was senseless. And it makes us think once again about how we can address the horrific problem of gun violence in America. The first task is conceptual -- can we figure out what will work? The second task is political -- can plausible solutions be implemented legislatively?
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A gunman went on a shooting rampage in a movie theater in Colorado
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John J. Donohue: Our gun policy is made by the NRA
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Look to Australia in formulating an effective gun control policy, he says
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Donohue: The question is, will our country ever unify against gun violence
Such would not be the case in the United States where pro-gun political views and @placeholder power create a very different climate.