Actually, the police tend to justify no-knocks saying that they are safer. I disagree, but that's what they will tell you.
Plus, it's a lame argument to say that the 4th amendment to the U.S. Constitution considers knocking on the door to be an actual part of the search itself.
The court gave its supporting arguments for the knock and announce requirement in Wilson v. Arkansas. It said, in a unanimous decision, that they gave the term reasonable the meaning given to it by the founders. Do you have evidence that this was not part of the intended definition?
Wouldn't it also be "reasonable" that the cops be in uniform to assure identification? That they use a marked patrol car? That they provide a phone number allowing the resident to verify the warrant with the judge prior to entry?
While some of these are probably good ideas, given that criminals have been known to pose as police in order to gain entry into a home, the "Castle doctrine" does not require any of them to my knowledge.
Should all these decisions be made by the U.S. Supreme Court?
Given that they all involve interpretation of the Constitution, sure. Why not?
I'm saying that "knock and announce" is in the cop's best interest in executing a run-of-the-mill search warrant. No-knocks are a whole different category, and this case wasn't about a court-authorized no-knock warrant.
"Do you have evidence that this was not part of the intended definition?"
Nope. And if the U.S. Supreme Court had any real evidence that it was part of the definition, they wouldn't have waited until just 10 years ago to announce it. Funny how all the previous courts missed it, huh?
"Given that they all involve interpretation of the Constitution, sure. Why not?"
Why not? Well, prior to your 1995 case, this was left up to each state. This is called federalism, though many have forgotten the concept.
But now we have a U.S. Supreme Court that, with the help of people like you, are more than happy to interpret the U.S. Constitution for all of us. Knocking is reasonable, sodomy and abortion are private, nude dancing and flag burning is protected speech but political speech before an election is not, a high school valedictorian saying "Christ" is establishing a religion, property is not yours but the city's, on and on.
These decisions are not being made by some State Supreme Court and applying only to that state. Oh, no. They're being made by our one-size-fits-all, screw federalism, five of us know better, U.S. Supreme Court and those judgments apply to all of us! Isn't judicial oligarchy fun?!
That's "why not".