The prospect of enormous profits from legalized gambling and prostitution proved to be a strong attraction for organized crime syndicates. In 1945 Bugsy Siegel, one of the most prominent of these criminals, began constructing the Flamingo, one of the city’s first casino and hotel complexes. He incurred a large debt with Meyer Lansky and other mob associates, and the first months of the Flamingo’s operation were shaky. It opened for good in March 1947, but Siegel was murdered shortly thereafter—according to one theory, at the behest of Lansky and other disgruntled investors—and Lansky immediately took over the business. The Flamingo’s enormous success encouraged more ventures, and several new casinos sprang up along what had become known as the Strip: the Thunderbird in 1948, the Desert Inn in 1950, the Sands and the Sahara in 1952, and the Riviera, the Royal Nevada, and the Dunes in 1955.

Although organized crime largely created contemporary Las Vegas, its dominance was short-lived. By the late 1950s the newly established Nevada Gaming Commission—which was responsible for licensing and overseeing gambling operations—began to curtail severely the freedom of gangsters to operate in the city. In the early 1960s the commission formulated its so-called “Black Book”; seeking to remove corruption from the gambling industry, the commission listed people with criminal records and banned from the casinos anyone listed in the book. Through vigorous enforcement of the law and the removal of corrupt public officials, the commission largely succeeded in separating crime organizations from the casinos, and corporations later took their place.

Also of importance to the development of the city were private individuals, among them Wilbur Clark, the owner of the Desert Inn, who proposed that the federal government retire its World War II–era debts by holding a national lottery, and Howard Hughes, who kept a suite at the Desert Inn throughout the 1950s and lived there permanently from 1966 to 1970. Some of the investments made by Hughes proved to be failures, including the costly Landmark Casino, which went bankrupt, but others were outstanding successes that brought Hughes vast profits. The Howard Hughes Parkway, a major thoroughfare that skirts the University of Nevada and McCarran International Airport, honours his many contributions to the city’s development.

The area also became well known in the 1950s and ’60s for the nuclear weapons tests conducted at the federal government’s Nevada Test Site, some 65 miles (105 km) from Las Vegas. At first the local populace responded favourably to these events, which could easily be seen by city dwellers; for a time, the atomic bomb’s mushroom cloud was even incorporated into the official seal of Clark county. Soon, however, protests were mounted against aboveground testing, forcing the government to conduct its experiments underground; Hughes, one of the most influential protestors, argued that open-air testing would drive visitors away from the city. It also became apparent in later years that exposure to nuclear fallout from those tests was yielding a high incidence of radiation-related cancers.

Las Vegas continued to grow in the 1960s, thanks in part to the publicity brought by such popular entertainers as Frank Sinatra, Sammy Davis, Jr., Wayne Newton, and Elvis Presley, all of whom became residents there. Its growth faltered only for a few years, beginning with a nationwide economic recession in the late 1970s; in addition, tourism declined after a fire at the MGM Grand Hotel killed more than 80 people in November 1980. Entrepreneur Steve Wynn, who had operated the Golden Nugget Casino since the early 1970s, used the downturn to acquire and renovate old casinos and build new ones, foremost among them the lavishly expensive Mirage, which opened in 1989.

In the late 1980s the city’s overall growth accelerated to match that of its gaming and tourist economy. The city’s population increased by nearly 100,000 between 1980 and 1990 to exceed a quarter million, and it surpassed the half-million mark early in the 21st century. The metropolitan area reached one million inhabitants in the mid-1990s and was well on its way to doubling that number a decade later.

The venerable Dunes was demolished in October 1993—in true Vegas tradition, as a spectacle in front of a huge crowd of onlookers. It was the last of the city’s 1950s-era hotels, and its destruction symbolically ushered in a new era of elite hotels, including the Venetian and the Bellagio. In addition, these new hotels were concentrated in fewer hands; the MGM Grand Corporation bought the Mirage Resorts Corporation in March 2000, effectively ending Steve Wynn’s chairmanship and bringing several major resorts under one corporate umbrella. Wynn, however, remained a presence in the city, opening a new casino resort complex in 2005. In a city that has long been characterized by such periods of sweeping growth and change, tourism and its vast array of ancillary services have provided Las Vegas with its most constant measure of continuity over the years.