Remind me again of the cause of Mexican violence?

[milktree]

It's because the US has liberal gun laws, right?

Um... it doesn't appear that way:

MEXICO CITY — Guards and officials at a prison in northern Mexico allegedly let inmates out, lent them guns and sent them off in official vehicles to carry out drug-related killings...

http://www.msnbc.msn.com/id/38405628/ns/world_news-americas