AlterNet: There is something especially unsettling about visiting Las Vegas these days — and it is not the town’s lascivious culture. A voyage to Sin City in this moment of ecological and economic crisis is a journey to a giant concave mirror reflecting back the magnified — and ugly — truths about this epoch of cataclysmic consumption and hubristic hedonism. Like most flights into Vegas, mine last week soared over a shrinking Lake Mead. Visually, the white strip around the manmade reservoir …