no country for old men redux (spoilers)

What's this movie/book mean? What is the point, as my high school teachers might ask. William Butler Yeats starts a poem, "Sailing to Byzantium" with the title of it:

THAT is no country for old men. The young
In one another's arms, birds in the trees
- Those dying generations - at their song,
The salmon-falls, the mackerel-crowded seas,
Fish, flesh, or fowl, commend all summer long
Whatever is begotten, born, and dies.
Caught in that sensual music all neglect
Monuments of unageing intellect.

An aged man is but a paltry thing,
A tattered coat upon a stick, unless...

The poem does seem to be similar in one sense to the book, the viewpoint of its chief narrator, the Sherrif: an old man feeling out of place in the world, unable to make sense of the changes going on in the country, even within his remote part of it: from bizarre killings, the remorselessness of some, and to people who have blue hair.

But then the other large theme in the story is that of chance. Chigurh offers to people the chance to live by the flip of the coin. The 2nd refuses, insisting it is his choice to kill her not the coins, but Chigurh replies, "but it's the same thing that brought me here" (or something very similar).

It was chance that let Moss miss his shot of the deer, chance that brought a bleeding dog across his path, chance that he came across the drug deal, chance that someone lived long enough to ask him for water, which brought Moss back to the scene. Chance that Moss's hunters came across him with the transponder. Chance is the only thing that near does in Chigurh.

I'm not sure quite what to make of either of these themes. The first, the lament of the old against present day evils is a shallow one, me thinks. It crops up a lot in the book, especially when the sheriff is conversing with other sheriffs, as well as in his narratives harking back to the old timers. Despite the fears and the real terrors, there are far darker places and have been far darker times to have lived than the here and now of the United States. Perhaps this lament is merely descriptive -- one story that might back that up is that of the Sheriff's crippled friend, describing how a relative was shot on his porch by Native-Americans.

The theme of chance on the other hand is a dark one to consider. I thought at first the final car crash was an ironic statement given the conversation with Moss's wife. But is it? In the book, Chigurh goes on to another appearance bringing the money back to one of the Players.

So is the view of the author's the view of Chirguh? Our lives are not pre-determined, we do not have freewill, there is only a continuous flipping of coins? If so then Chigurh is the only one fully prepared, the one who leaves nothing to chance, as methodical as the police in taking what information he can use, methodical in executing the whims of the world, ready to take on whatever comes his way.