Very brief protest against pay, perhaps to do with response to nuclear attack (6-6)

'very brief protest against pay perhaps to do with response' is the definition.
I know nothing about this answer so I can't tell whether this works.

'nuclear attack' is the wordplay.
'nuclear' becomes 'second' (I can't explain this - if you can you should believe this answer much more).
'attack' becomes 'strike' (strike is a kind of attack).
'second'+'strike'='SECOND-STRIKE'

'to' acts as a link.

Can you help me to learn more?