The focus of the analysis of the Las Vegas shooting has now become bump stocks—and the gun lobby is seizing on it as a solution. It is a red herring and banning bump stocks will accomplish nothing. 
The real culprit in this situation is allowing magazines of 20, 30, and 50 rounds. Who other than the police or the military needs that many rounds to be fired in rapid succession? Bump stocks just make use of these large magazines to approximate a fully automatic weapon. Bump stocks are actually unnecessary as these weapons with large magazines can be bump fired without the bump stocks. 
If Americans are truly in search of a solution to mass shootings of this order, then it is magazines of more than five rounds that should be banned.