Whales raised on the endless beach close to Connecticut too important to touch (10)
I believe the answer is:
Here is my best explanation:
'too important to touch' is the definition.
(I've seen this before)
'whales raised on the endless beach close to connecticut' is the wordplay.
'whales' becomes 'orcas' (orca is a kind of whale).
'raised' says the letters should be written in reverse.
'on' means one lot of letters go next to another.
'the endless beach close' becomes 'san' (I can't explain this - if you can you should believe this answer much more).
'to connecticut' becomes 'ct'.
'orcas' written backwards gives 'sacro'.
(Other definitions for sacrosanct that I've seen before include "Unchallengeable", "inviolable", "Too valuable to be changed", "Too valuable to touch", "Untouchable", "Inviolable", "above criticism", "Too important to touch", "Revered, untouchable" and "Co-stars can (anag.)".)