How much truth is there to belief that the Mob built Las Vegas?

Finally, something in my area of expertise. I've written fairly extensively on this. Sources: A few books I've written, including Suburban Xanadu: The Casino Resort on the Las Vegas Strip and Beyond, and Roll the Bones: The History of Gambling, as well as lectures I've given for my courses on the history of casinos and the history of Las Vegas and around town. Mods, if I need to provide proof, please let me know. Long-time lurker, first time poster on this sub.

First, we need to be clear about what "the Mob" and "Vegas" mean. First, Vegas. Las Vegas was founded in 1905 by the Salt Lake, LA, and San Pedro Railroad, simply because it was the best place for trains heading from SLC to LA to stop to take on water. In its first years, Las Vegas was a completely ordinary small railroad town. After the Union Pacific bought the SLLASP and, following a strike, moved its repair shops up to Caliente, the town entered a decline that was reversed with the construction of Hoover Dam. The federal government would go on to provide much economic development for the area, particularly with Nellis AFB and the Nevada Test Site. So it was a railroad that "built" Las Vegas and the federal government that sustained it.

What is the Mob, then? Lets use it as shorthand for organized crime, particularly the organized crime that emerged around Prohibition in the 1920s. It was not one cohesive group following a unified objective, but rather a group of semi-independent actors. See Joseph Albini's work for a more thorough discussion of this.

In Mark Haller's interpretation, the cohort of mobsters who came of age during Prohibition dominated because they were young and aggressive. They were mostly born around 1900. By the 1940s, they are in their forties and looking for respectability.

Nevada had legalized "wide-open" commercial gaming in 1931 as what historian Eric Moody calls "purely a business proposition." Hotel owners and other small-time business people lobbied the legislature to do this to bring in more tourists. Reno was the biggest gambling center, with Las Vegas an afterthought.

In the 1940s, though, operators began constructing self-contained casinos resorts on land south of Las Vegas that eventually became the Las Vegas Strip. These required extensive capital investments and marketing. The problem was that mainstream lenders would not lend to casino projects (too risky). The best places for capital were with those who knew the gambling business already. This was Haller's cohort, many of whom moved from rumrunning to illicit gambling after the end Prohibition.

So by the late 1940s and early 1950s, this group of middle-aged former rumrunners moves into Las Vegas. Moe Dalitz and his associates in the erstwhile Mayfield Road gang are the best example. In addition to building and running casinos, they undertake developments around the city, ranging from Sunrise Hospital to housing subdivisions.

Casinos with a connection to the mob have three advantages: they can get capital more easily than "clean" casinos; via junketing through local illegal gamblers, they can get sources of willing gamblers; and they have a distinct advantage in debt collection (which at the time Nevada law prohibited). So these casinos thrived.

As the industry got bigger in the 1960s thanks to a turn towards the convention trade and as Haller's cohort aged out, publicly-traded corporations began to dominate. Hilton Hotels bought Kirk Kerkorian's casinos in 1971/2, and other "indigenous" operators like Showboat and Harrah's went public. Changes to the law and the increasing acceptance of casinos as investments eliminated the mob's three advantages, so by 1985 at the latest, mob-related figures were (mostly) out of the ownership of Las Vegas casinos.

TLDR: the Mob didn't build the city itself, but was extremely influential in its gaming industry, particularly from about 1945 to 1975.

Happy to answer any related questions, rules permitting.