To what extent does Buddhism teach non-violence?

http://www.nytimes.com/2015/01/03/opinion/sri-lankas-violent-buddhists.html?_r=0

https://www.colombotelegraph.com/index.php/full-text-of-the-banned-time-story-the-face-of-buddhist-terror/

http://www.buddhanet.net/e-learning/buddhism/dp10.htm