10th Amendment: "The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people."
You can look as hard as you want you will not find policing powers delegated to the US government within the Constitution. Ergo police powers, that is the power to regulate behavior and enforce order within their territory for the betterment of the health, safety, morals, and general welfare are reserved to the State.
Moreover, " nowhere in the federal Constitution is Congress given authority to regulate local matters concerning the health, safety, and morality of state residents. Known as police powers, such authority is reserved to the states under the Tenth Amendment." (See: http://legal-dictionary.thefreedictionary.com/Tenth+Amendmen...)
In fact your comment proves my point that people accept Federal police power without question, to the point you make an legal argument supporting your point of view (and that of the US Gov.) and provide no support, other than stating "there is no such provision anywhere in the Constitution"
No, they weren't. There is no such provision anywhere in the Constitution. The states are sometimes described as being different than the federal government under the federal Constitution because the former have general police powers while the latter has limited powers, but the key distinction there is "general" vs. "limited"; both have police powers.