The worst evils of the 20th century were done by people with lots of scientific, industrial and psychological knowledge propping them up. And the worst evils of the 21st century will be no different.
No, there is quite some evidence behind that idea[1].
[1] http://www.ted.com/talks/steven_pinker_on_the_myth_of_violen...
OK, find me a duel and a bear-baiting match in America and I'll believe you. Otherwise you're just mindlessly cynical, like any number of other teenagers.
You're probably right about bear-baiting. But there is plenty of organized dog fights and cock-fights around.
As for your link, an anecdote does not data make. If you want to argue that our society is getting more violent you need to prove that the amount of violent episodes now is higher than in the past, not that there happen violent events now. And as a matter of fact, overall in most of the Western world, the amount of violent crimes has been on a steady decline for the last 50 years at least (the amount of other crimes has gone down too, by the way).