The Tucson shooting was predictable, and not because of heated Left-Right political rhetoric (which Obamalot helped create and cannot solve) but due to an older, never-resolved political mistake.
“These tragedies are the inevitable outcome of five decades of failed mental-health policies. During the 1960s, we began to empty the state mental hospitals but failed to put in place programs to ensure that the released patients received treatment after they left.
“By the 1980s, the results were evident—increasing numbers of seriously mentally ill persons among the homeless population and in the nation’s jails and prisons.”
You can see the results on any Austin street corner, i.e. the bums out cadging money from motorists. Some of them are too lazy to work, or have serious alcohol or drug addictions. But more have the dazed, out-of-it look of the mentally lost. Or the damned.
THE TEXAS SCRIBBLER 
And let’s not forget the gun sale. This character was so obviously crazy and has so many ticks against his name, and still he got through the approval process. Obviously something doesn’t work as it is supposed to.
You’re surprised that government fell down on the job? The problem here is that gun ownership is either a right or it isn’t. And if it is (and it is), then it takes consistent enforcement (with understandable and, preferably short, paperwork for the seller) to make exceptions. Government, being notoriously lazy, is rarely consistent.
Probably this will follow the usual pattern: the law, having failed, will be amended. And when it fails next time it will be amended again, adding to the complexity of the paperwork. Always a new law, then a new failure, then another new law. Only the career pols win.