Thanks for the interesting conversation, jacobolus - but I'm pretty confident that you didn't spend your childhood in colonial society. I think what you mean is that you spent your childhood in a society whose class disparities were vaguely comparable, at least in an ideologically stereotypical way, to colonial society.
(Note that in all Latin American countries, including frickin' Cuba, the governing caste looks like Gael Garcia Bernal and the governed caste is black, brown or both. See under: "Subcomandante Marcos." After the 20th century it should be difficult for any ideology to claim it has some magic solution to this particular problem.)
Without of course disputing the actual reality you've experienced, I would suggest two ways of interpreting this perspective.
One is that the constant low-level violence in these postcolonial societies is not a consequence of how similar to actual colonial societies they are, but how different they are.
You don't see constant low-level violence when formal power is identical to informal power. When the patron is actually an encomendero, there's no reason for forced labor (the distinction between "forced" and "unforced" labor is pretty academic to an unskilled agricultural laborer - either way, he has to work or he doesn't eat) to involve violence, because he has the formal right to command and can call on the lawful arm of the state to assist him.
Whether or not he should have this right, or rather power, is a separate question. But note what happens when you try to eradicate these feudal structures, which of course did not arrive with the Europeans but predate them: you're driving Nature out with a pitchfork. When the patron is just a big man, not an actual government official, his power is not in the form of policemen and soldiers, but thugs and more thugs.
Second, reinforcing this argument, consider the fact that everything you know about the colonial period comes from the enemies of colonialism. Imagine if everything you knew about Jews came from people who hated Jews. Every time a Jew committed some crime or abuse, this would be played up at maximum volume and associated with the entire Jewish race. Exactly how the Goebbels press worked.
In other words, the 20th century image of colonialism is just an extension of the good old Leyenda Negra tradition. I don't have to explain this to you, but for others:
http://en.wikipedia.org/wiki/Black_Legend
I agree - the story is very sad. I hope Mexico can find its way to a new Porfiriato sometime soon. The first step would definitely be expelling the US Embassy - and taking every other possible measure to pretend there's nothing but ocean north of the Rio Grande.
Mexico is blessed with energy and food security, so it really does have the physical strength to tell Washington where it can put all its fatherly advice. And we're certainly in no political condition to invade you! So the main thing that's missing is cultural self-confidence.
Perhaps it's not too late to reinvent some kind of Franquista Hispanidad, Falangism, sinarquismo, etc:
http://en.wikipedia.org/wiki/Mexican_synarchism
Until that point, I'm quite confident, the beheadings etc. will continue. Political order is something you take for granted until you find you don't have it, and then it's quite difficult to restore without applying a level of force comparable to that at the disposal of the disorderly.
Or to put it differently, after its century of revolution, Mexico needs martial law the way a camel that's just walked across the Sahara needs a drink of water. It's not alone in this. A friend of my wife's recently spent nine months in Guatemala City on a State Department journalism fellowship. She left as impeccable a progressive as you'd ever see. She came back with the most amazing good words for dictators and dictatorship. If you know Guatemala City, you know why...
Erna Fergusson, an American no less progressive, visited Guatemala in the '30s and wrote this book:
http://books.google.com/books/about/Guatemala.html?id=fv5kAA...
She describes Guatemala as "like Mexico before the Revolution." Politically this is certainly the truth. And the capital, for instance, is described as impeccably clean and crime-free. This did not fit the author's agenda, but was just what she saw. Again, compare!