[OneWingedShark]

These authorized home invasions need to stop except in exceptional circumstances.

That's where you're wrong — the Constitution puts a flat prohibition on such.
IOW, to admit that there are extenuating circumstances which invalidate the 4th is to render the 4th into a arbitrarily-applied selective law.

[Sherman Logan]

The 4th prohibits "unreasonable" search and seizure without a warrant. It does not of itself specify the type of entry.

No-knock forceful entry entirely appropriate in some circumstances.

Or do you think police should approach a hideout for heavily armed terrorists by politely knocking on the door? Perhaps one where hostages are being held?