As the country tried to find comfort and make sense of Friday's mass shootings in Newtown, Connecticut, the focus began to shift from sympathy for the families of the 26 victims to outrage over how such a tragedy could have happened in the first place.
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What's to blame for this and other recent mass shootings in the United States? There are no easy answers, but Americans are pointing their fingers at several possibilities.
Too many guns. Republican Senator Joe Manchin of West Virginia, a conservative member of the National Rifle Association who posed with a rifle and promised to protect the Second Amendment in his election campaign videos, said on Monday that it's time to reconsider our nation's gun laws.
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"I'm a proud outdoors-man and huntsman, like many Americans, and I like shooting, but this doesn't make sense," he said on MSNBC's "Morning Joe." "I don't know anyone in the sporting or hunting arena that goes out with an assault rifle. I don't know anybody that needs 30 rounds in a clip to go hunting. I mean, these are things that need to be talked about."
"Seeing the massacre of so many innocent children has changed everything," Manchin added. "Everything has to be on the table and I think it will be."
Not enough guns. The National Rifle Association took down its Facebook page, went silent on Twitter, and told CBS News that "Until the facts are thoroughly known NRA will not have any comment" on the mass shooting. The National Shooting Sports Foundation (NSSF) called the shooting a "horrible tragedy". And all 31 pro-gun members of the U.S. Senate turned down invitations to defend their points of view on "Meet the Press" on Sunday. But some gun advocates, like Republican Representative Louis Gohmert of Texas, are saying that the shooting could have been prevented if more responsible adults in the area -- like principal Dawn Hochsprung, who was killed when she confronted the gunman -- had been armed themselves.
"I wish to God she had had an M-4 in her office, locked up so when she heard gunfire, she pulls it out and she didn't have to lunge heroically with nothing in her hands," he told Fox News on Sunday. "But she takes him (the shooter) out, takes his head off before he can kill those precious kids."
Some Conntecticut residents agreed.
"The gun is not the issue. If someone else there had a gun, maybe they could have stopped this," Benjamin Torres, owner of Betor Roofing in Danbury, told Reuters on Monday. "The bad guys are going to get guns illegally anyway."
"Personally, I feel safer where there's guns," 19-year-old Peter Griffin, an apprentice cabinetmaker who owns three guns, told Reuters while shopping in the hunting section of a Dick's Sporting Goods in Danbury. "I don't want to go to any gun-free zones any more."
A need for better gun laws. The guns used in Friday's mass shooting were legally purchased and licensed -- albeit to the shooters mother, who was his first victim. Nancy Lanza was shot four times in the head with one of the many guns she kept in her own home for protection. Current gun laws do not require applicants to disclose whether the applicant has ever voluntarily undergone treatment for mental illness, or whether someone with mental illness lives in the home where the guns will be kept.
Data from 2011 shows that the majority of Americans support bans on high-capacity ammunition clips (which hold more than 10 bullets) and on AK-47-style assault rifles, think that all gun purchasers should undergo background checks to see if they've ever committed a felony, agree that gun-owners should have to register their weapons with local government, and that the mentally ill should not be allowed to possess firearms. According to a CNN survey, a slim majority of Americans are opposed to limiting the number of guns a person can own.
Mental illness and autism. Earlier this year, Colorado Governor John Hickenlooper said that tougher gun laws would not have prevented the mass shooting that killed 12 and wounded 58 others in a movie theater in Aurora, Colorado, in July. Though he now says that he's willing to discuss restricting high-capacity magazines, he feels that educating people about mental illness and supporting those who are dealing with mental health problems could be a better way of addressing violent tragedies.
"That's something we can do immediately without getting into some of the battles of gun legalization or restricting access to guns," Hickenlooper, a Democrat, told CNN.
The Sandy Hook school shooter's brother, Ryan Lanza, told ABC News that his younger brother "is autistic, or has Asperger's syndrome and a 'personality disorder,' prompting many to wonder whether there could be a link between violent behavior and autism.
According to Eric Butter , a psychologist at Nationwide Children's Hospital in Columbus, Ohio, some people with autism do exhibit aggressive behavior, but it's typically limited to outbursts of shoving, pushing, or angry shouting. "We are not talking about the kind of planned and intentional type of violence we have seen at Newtown," he told the Associated Press.
"People want immediate or simple answers when an unimaginable tragedy like this occurs," Bob and Suzanne Write of Autism Speaks said in a statement on Monday. "Autism did not cause this horror. The profound tragedy of these senseless murders will only be compounded if it results in unwarranted discrimination against people with autism."
A lack of support for parents. In an essay that went viral over the weekend, mother of four Liza Long wrote about what it's like to parent a child with mental illness.
"I love my son," she said of her 13-year-old. "But he terrifies me."
"When he's in a good mood, he will gladly bend your ear on subjects ranging from Greek mythology to the differences between Einsteinian and Newtonian physics to Doctor Who. He's in a good mood most of the time," she wrote at The Blue Review. "But when he's not, watch out. And it's impossible to predict what will set him off."
He screams insults and has threatened to kill her -- and himself -- more than once. His 7- and 9-year-old siblings know to lock themselves in the family car when he gets violent. He's spent time in the ER and in mental hospitals, been diagnosed with a host of disorders, been on antipsychotic and mood-altering drugs, subjected to strict behavioral plans. And nothing has worked. His social worker says that the best way to get help for her son would be to have him charged with a crime, to create a paper trail. "No one will pay attention to you unless you've got charges," she was told.
Hundreds of responses to the essay show that Long is not alone. Still, amid the outpouring of compassion are plenty of comments and blog posts calling her an unfit parent, accusing her of hiding her own history of mental illness and violent tendencies.
The media. A statement in which Academy Award-winning actor Morgan Freeman criticized the media for sensationalizing tragedies went viral over the weekend and, while Freeman denies that the quote was his, plenty of people agree with it.
"It's because of the way the media reports it," the hoax statement read. "Flip on the news and watch how we treat the Batmantheater shooter and the Oregon mall shooter like celebrities. Dylan Klebold and Eric Harris are household names, but do you know the name of a single victim of Columbine? Disturbed people who would otherwise just off themselves in their basements see the news and want to top it by doing something worse, and going out in a memorable way. Why a grade school? Why children? Because he'll be remembered as a horrible monster, instead of a sad nobody."
Violent video games and pop culture. Could the popularity of first-person shooter video games, violent movies, and TV shows that glorify killing have desensitized Americans?
"There might well be some direct connection between people who have some mental instability and when they go over the edge - they transport themselves, they become part of one of those video games," Hickenlooper said on CNN's "State of the Union." "Perhaps that's why all these assault weapons are used."
A need for more religion in schools. On Friday, former Arkansas governor and presidential candidate Mike Huckabee told Fox News that a lack of faith has led to an increase in school violence.
"We ask why there is violence in our schools, but we have systematically removed God from our schools," he said. "Should we be so surprised that schools would become a place of carnage?"
It echos his remarks after the Aurora, Colorado shooting, when he told Fox News: "We don't have a crime problem, a gun problem or even a violence problem. What we have is a sin problem. And since we've ordered God out of our schools, and communities, the military and public conversations, you know we really shouldn't act so surprised ... when all hell breaks loose."
Still, on Monday he walked back his comments, explaining that what he meant was "we've created an atmosphere in this country where the only time you want to invoke God's name is after the tragedy."
Other groups say that the focus needs to be on the people themselves, not religion.
"Our hearts go out to the families of the victims and to all of those affected by this devastating event," Edwina Rogers, executive director of the Secular Coalition for America, told Yahoo! Shine in a statement. "No family-no child-should ever have to experience a tragedy such as this."
Also on Shine:
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The Connecticut Shooting Makes Me Want to Cry, Yell, and Hug My Child
Newtown Shooting's Child Witnesses