You can certainly execute an attack without using the periscope (this was already possible at the end of WW2, using the type XXI detection and ranging system)
And b.t.w. i think a camera on an extractable arm, is still a periscope.
But thinking of what would happen nowadays, if you screwed up the identification for whatever reason, a short verification via periscope (or via some drone)
would be done, before firing.
OT
Quote:
Originally Posted by Aktungbby
...The Royal Navy...(the last is best). HMS Conquerer, 1982, an attack nuclear submersible famously attacked and sank the Argentine vessel, Admiral Belgrano-formely the USS Phoenix, launched 1938, a light cruiser.... 
|
" .. As a result Mrs Thatcher and her War Cabinet, meeting at Chequers the following day, agreed to a request from Admiral Sir
Terence Lewin, the Chief of the Defence Staff,
to alter the rules of engagement and allow an attack on General Belgrano outside the exclusion zone."
Which was done, still controversial today. Anyway the whole Argentine idea of taking back their 'Malvinas' was not a very clever one.