Pew's Project for Excellence in Journalism looked at blogs, at tweets, and at newspapers. A discussion of gun policy dominated the social media conversation, and "calls for stricter gun control measures exceeded defenses of current gun laws and policies by more than two to one." On the editorial and op-ed pages of the 11 papers Pew examined, the reaction was even more lopsided—more than six columns and editorials calling for stricter laws for every piece defending the laws we've got.
Pew tells us this focus on legal reform is far different from what followed the Tucson mall shooting in January 2011 in which six persons were killed and Congressman Gabrielle Giffords was gravely injured, and the shooting of teenager Trayvon Martin by a security guard in Florida last February.
Pew doesn't attempt to say why. We can conjecture. The age and innocence of the victims are clearly a big factor. So, possibly, is the fact the country just had its elections, so our reaction could remain unwarped by politics. And perhaps also helping shape the reaction is our knowledge that gun control wasn't even on the table in that election—Second Amendment absolutists had won every battle, silencing the opposition. The national horror at the actions of Adam Lanza might be laced with a measure of self-revulsion at all the ground that had been surrendered. The laws Americans have wiped out may or may not have stopped Lanza, but at least they were a codified expression of where a lot of Americans, when they still had voices, used to say they stood.
Here's the Pew report.