Bond perhaps needs cover for official crackdown (8,7)
I believe the answer is:
security blanket
'official crackdown' is the definition.
(measures to crack down on state secrecy)
'bond perhaps needs cover' is the wordplay.
'bond perhaps' becomes 'security' (bond is a type of security).
'needs' means one lot of letters go next to another.
'cover' becomes 'blanket' (blanketing is a kind of covering).
'security'+'blanket'='SECURITY BLANKET'
'for' is the link.
(Other definitions for security blanket that I've seen before include "child's favourite recourse" , "comforter for child" , "Embargo on information" , "It may help one sleep at night" , "comforting to the young?" .)