Generally, no. There are 3 types of casinos in the US. Private casinos, Indian casinos, and lottery casinos. Private casinos, like those in Las Vegas, are individually owned but regulated by the state gaming office, and pay hefty taxes on all earnings. Indian casions, like those in Oklahoma, are on Indian reservation land, and are owned and regulated by the tribe. Anyone can play, and the casino earnings are tax-free. Lottery casinos, like those in Oregon, are joint state/private affairs. The machines are owned and operated by the state lottery board, and they are leased to a bar/restaurant, who gets a percentage of the take.
In all states, gambling is strongly regulated. Some states, such as Texas, don't allow any gambling at all, not even Indian casinos. In most states, casinos are allowed, but the regulations are so strong that there isn't any way to turn a profit. The Indian casinos, which can bypass regulations (but not prohibitions), are popular in those states. Kentucky does not allow card games or casino machines, but it does allow track betting. There are 8 tracks in Kentucky where one can bet on horse racing. Doubtless, these tracks are strongly regulated and taxed by the state.
In Louisiana and Mississippi, there are riverboat casinos. These casinos get around some state regulations because they are not fixed locations. In fact, some parts of the river are not in either state. This led to waterfront gambling throughout Louisiana, which is now a strongly taxed and thriving industry. Such a situation is a good place to start talking about online gambling. Because the physical location of the server is in a state that allows gambling, it is theoretically legal. If a person in Kentucky is gambling online, where is the gambling actually taking place? There are 3 possible choices - it is taking place in Nevada, where the server is; it is taking place in Kentucky, where the client is; or it is taking place in a nowhere space that cannot be regulated by the state.
Up till now, online gambling has taken place in that 3rd space that cannot be defined and has not been regulated. Apparently, the governor of Kentucky has taken it upon himself to just sorta decide that he has jurisdiction. Which is a dangerous idea - if internet activity can be officially localized, it can be regulated by the state - we could see porn domains seized next. Plus, what about people in states where online gambling is legal - are they fucked now because Kentucky has shut them down? This is not going to end well.
It is generally accepted that increased gambling leads to increased gambling addiction, in the same way that more cars leads to more car accidents. Gambling, much like drugs and prostitution, is mainly illegal because we don't want people to think this sort of behavior is okay.