All the usual suspects.
http://www.huffingtonpost.com/paul-helmke/giffords-shooting-is-amer_b_806254.html"...While we are all still learning details about this shooting, and particularly the 22-year old responsible for this horrendous act, we should find it unacceptable that when Americans and our elected leaders are assembling in public places, their lives are at risk from gun violence.
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We, as Americans, can and should do more to restore civility to our political discourse. And we can and should do more to address the easy access to high-powered guns that make it too easy for dangerous and irresponsible people to disrupt and destroy the lives of innocent Americans, and political leaders who are simply trying to serve their communities and our country."
http://www.huffingtonpost.com/josh-sugarmann/congress-must-rein-in-gun_b_806264.html"Congress Must Rein in Gun Industry in Response to Giffords Assassination Attempt
So far few facts are known except the most horrifying: A Member of Congress is shot in the head while reaching out to her constituents and is rushed to surgery; six others are shot to death, including a judge and a nine-year old child; numerous others are injured.
America's gun culture claims its latest victims.
Initial news reports are that the man who shot Arizona Representative Gabrielle Giffords and others used a Glock semiautomatic pistol equipped with an extended magazine -- such magazines can hold up to 32 rounds of ammunition that can be fired without reloading.
These high-capacity ammunition magazines were banned before Congress allowed the federal assault weapons ban to expire in 2004. Despite protests by law enforcement and public officials, the gun lobby and its supporters on Capitol Hill dismissed the ban on assault weapons
and high-capacity magazines as an infringement on their right to own any gun of their choice -- no matter the risk to public safety."
http://www.huffingtonpost.com/jeff-biggers/lock-and-load-and-lost-in_b_806267.html"Tucson, Arizona--I was 8-years-old in Tucson when I first had a firearm pressed into my hands at a summer camp, and I locked and loaded and fired.
I thought about that strange first gun experience when I heard the initial confusing news reports of the shooting of US Rep. Gabby Giffords and 17 other Arizonans at a Safeway supermarket on the northwest side of town I have frequented often. I immediately headed for the university hospital.
On the drive over, I was reminded by a Tucson friend that it has been less than a year since Arizona Gov. Jan Brewer made her state one of three in the nation to allow citizens to possess concealed weapons without a permit for those over the age of 21."