Yes, life is tenuous, chaotic, random and dangerous. No, 100% security and safety can't ever be guaranteed. But you're talking about the gun lobby, the pilot program for convincing* Republicans to misread the Second Amendment, worship gun ownership as a right, and above all keep repeating that this is simply a matter of partisan politics, not lives lost.
* (Just like healthcare, just like taxes on the top 1%, just like corporate personhood or same sex marriage: Any way a corporate entity can sell you on voting against your own self-interest, it's going to come down to either making it seem like "politics as usual" -- which goes right to false equivalencies, which are the GOP's lifeblood because everybody turns off their minds when it goes there -- or an endemic issue of humanity, with religious or patriotic significance.)
I think it's very sad that this poor boy went crazy and hurt people, and I agree that it's random. Completely random. But pinpointing blame for the parts of the situation that are avoidable? "Politicizing" it? You bet your ass; it's already political. That's because at hear it's not politics, it's a rational progression of thought, and a natural one.
As a corporate entity, partisanship is part of the game because there's no ideology beyond more, more, more: They can troll, pushing for 100% deregulation they'll never get, so that we get tied up in policy and "we'll never be completely safe," false-equivalency mobius loops. Money, generating a strapped-together belief system from the contradictory pieces of what you need to be sold, by acting on the most selfish and privileged parts of your personal existence. All true. But really, in this case it's much simpler than that:
The NRA has one mandate, which is to make sure that Americans like James E Holmes don't have their rights -- to keep and bear arms -- infringed.