"Have the Americans accepted that gun crime is a price worth paying to be able to hold arms?"
Loaded question fallacy.
This is a mental health issue, not a 'gun' issue, having nothing to do with gun control, gun laws, or the Second Amendment.
There are two fundamental elements in play with this and other like incidents: the unwillingness or inability of Americans to implement comprehensive mental health programs and policies, and the inherently violent nature of American society, where violence is perceived as a legitimate means of conflict resolution.
Second Amendment jurisprudence in no way 'facilitates' gun violence, it concerns solely safeguarding the right to possess a firearm pursuant to the right of self-defense from unwarranted government regulation and interference – and rightfully so given the wrongheaded notion that crimes such as that which occurred in Oregon are the result of 'too many guns' that are 'too easily' acquired.
The resolution to this problem will be realized through the political – not legal – process, where the American people must insist in the funding and implementation of comprehensive mental health programs and policies and address the violent nature of American society.
The American people lost the ability to defend against their own government 100 years ago. This fantasy that being armed with a semi-auto rifle will give us the ability to fight our own military if necessary is just childish nonsense. As soon as a platoon of A1 Abrams tanks rolls into town the fight is over. Not to mention the helos, jets, missiles, intel, satellites, aircraft carriers, and thermo-nuclear bombs.
Anyone who thinks we have a right to bear arms to 'protect our liberties' is living in lala land. That shite ended long ago.
All this idea now is, is a way to feel warm and fuzzy and 'like our forefathers who yada yada'... It is a falsehood.