In his home state, Reid often leaves the local green movement seeing red, for he is the godfather of and rainmaker for the two Nevada industries—the casino-real-estate-development nexus and hard-rock mining—that critics say are the state's leading despoilers and polluters. He was the guiding force behind shelving mining-law reform in a Senate-House conference committee in 1994, allowing several of the world's biggest mining companies to continue denuding and dewatering large swaths of northern Nevada. (Reid, in a written statement, said he hopes to support some mining reforms in the current Congress.)

Even some of his high-profile wilderness protection plans have come at a high price, bundled as they are with federal land sales that give developers access to vast acreage once off-limits to building. "Whatever Las Vegas wants, Las Vegas gets, and Harry Reid makes sure that happens," says Janine Blaeloch, founder of Western Lands Project, a Seattle nonprofit that has closely monitored the senator's sell-off of government land for Las Vegas growth. "What's so dismaying is that he gets away with it, because the big environmental groups are bought in."

Indeed, some environmentalists worry that what's happening in Las Vegas can be seen as a harbinger of looming water crises in many fast-growing areas across the country. "The decision to pursue this kind of water transfer is, in part, a decision to avoid a debate about urban growth that cities like Las Vegas need to have," says Peter Gleick, president of the Pacific Institute, in Oakland, California. The think tank recently co-authored a study that found that Las Vegas, through more conservation, could save nearly as much water as it plans to take from central Nevada. "How fair is it to look for more and more water, farther and farther afield, when we're using the water we have improperly?" Gleick asks.

The pipeline idea stems from a mind-set in Southern Nevada that embraces growth at any cost. In the summer of 2007, residents of northwest Las Vegas were livid when the developer of the sustainable community planned near Mount Charleston proposed building a high-rise casino in the heart of the new suburb. Despite a rare flare-up of grassroots opposition, the proposal cleared the Las Vegas City Council, carried by the district's own councilman, who doubles as a leader of the powerful Southern Nevada construction union.

In a transient city, where many people come to start over or retire, few residents seem to pay much attention to civic affairs; turnout for municipal elections in June was 8 percent. So Southern Nevada is essentially run by a plutocracy of 50 gaming and real estate bosses and their anointed political friends, says one longtime Reid observer. "Everybody who's in that group of 50 people has an interest in more growth," this person says. "It's a growth and extraction culture."

Reid, who declined to be interviewed for this article, is unquestionably a political paradox. The senator prides himself on being a bridge between the old West of his hardscrabble childhood, with its rugged libertarianism and shattered dreams, and the new West of order and opportunity in the Las Vegas suburbs. He was born in 1939, in a busted-down mining town called Searchlight, 58 miles south of Las Vegas. Never bountiful, Searchlight's gold and silver mines had given out in the early 1900s, "leaving behind the diehards, the outcasts, the mavericks, or those too old or too sick to move on," Reid wrote in a 1998 book about his hometown. Whorehouses and gambling halls were Searchlight's mainstays. The town's first pool was built by a bordello owner for his prostitutes but was open to kids one day a week.