In concert with fellow Nevada senator John Ensign, Reid radically changed the rules for privatizing Western lands. Until the late 1990s, Congress limited the federal land agency to disposing of no more than 700 acres a year in the Las Vegas Valley, all within a relatively small area surrounding the city's center. Starting in 1998, Reid co-sponsored laws pushed through by Nevada's congressional delegation that enlarged the B.L.M.'s "disposal boundary" in the valley all the way to the foot of the mountain ranges outside the city. The 78,000 acres of land designated for the auction block—an area equivalent to roughly half the developed acreage in all of Clark County—unlocked the valley to metropolitan sprawl as far as the eye could see. Since 1998, builders have blitzed the county with more than 244,000 new housing units, a 50 percent surge in the county's housing stock. The influx of new residents to Clark County has run as high as 6,000 a month—or one every seven minutes. Yet most environmentalists looked the other way, because as part of legislation disposing of the Las Vegas Valley land, Reid and other members of Congress helped extend federal wilderness protection to 452,000 acres of mostly mountainous terrain in Southern Nevada. "We were naive," says Jane Feldman, of the local Sierra Club chapter, who flew to Washington in 2002 to lobby Congress for what she thought was a wilderness bill. "We underestimated the processes that would force the B.L.M. to auction off those lands for development. We're paying for this astronomically." Feldman says she once confronted Reid at an environmental meeting about the impact of urban sprawl. He told her that the federal government couldn't do much about it and suggested she talk to his eldest son, Rory, now chairman of the Clark County Board of Commissioners, which has wide discretion over land-use decisions.

I met Rory Reid at his day job, at the offices of Lionel Sawyer & Collins, Nevada's biggest law firm. Harry Reid's four sons—ages 33 to 45—have all worked for the firm, which represents many of the state's major casinos, developers, and mining companies. (Rory is also the Nevada chairman of Hillary Clinton's presidential campaign.) A graduate of Brigham Young University and its law school, Rory has the same earnest bearing that has long burnished his father's reputation as Nevada's "Mr. Cleanface." (The moniker reportedly came from a Kansas City mobster, who boasted on an F.B.I. wiretap in the late 1970s that he had Mr. Cleanface in his pocket. The F.B.I. investigated Reid, then chairman of the Nevada Gaming Commission, and found no basis for the claim.) Rory, who is also vice chairman of the Southern Nevada Water Authority, says it's nonsense that he or his dad coddle developers; the region's growth is driven by "huge economic forces" that politicians can't easily control. Southern Nevada needs the Great Basin's water, he says, to ease its dangerous reliance on dwindling Lake Mead. "If not this, what?" Rory asks.

The Great Basin pipeline route extends north from Las Vegas alongside U.S. 93 into the majestic Coyote Springs Valley. The mountain-rimmed plain, about 50 desolate miles north of the city, is the site of one of the most ambitious desert development plans ever undertaken in Nevada. In 1998, one of Reid's closest friends, Harvey Whittemore, gained control of 43,000 acres of raw Coyote Springs Valley scrubland from a defense contractor that decided not to use the area for a missile range. Whittemore, a senior partner at Lionel Sawyer who was once ranked Nevada's most powerful lobbyist by the Reno Gazette-Journal, drew up plans for a whole new city in the desert, a metropolis with 159,000 homes, 5,700 acres of commercial development, and 15 golf courses. To proceed, however, he needed to get rid of a mile-wide federal right-of-way for electric-power lines that, as title maps showed, ran right through the property.