You're attempting to imply that HSBC was an innocent party, and that's simply nonsense.
HSBC was fined because it failed to follow the rules put in place to prevent money laundering. Often it completely failed to make any attempt to follow those rules. E.g.
"...The monitor’s findings described several incidents, among them one where an HSBC branch in Sinaloa, a Mexican state that has experienced much drug-related violence, opened a private-wealth account for a 19-year-old man who arrived with a bag containing thousands of dollars in cash. The man described himself as a shrimp farmer."
http://www.wsj.com/articles/hsbc-struggles-to-bring-money-la...
There was a consistent pattern of failing to flag, investigate, or report transactions that were clearly suspicious.
That's why HSBC was fined. There's no grey area here, and the laws aren't particularly onerous. They were simply ignored.
>it could trigger a collapse of the entire financial system as bankers exited the industry en-masse.
Considering the close association between banks and fraud/criminality, that would hardly be a bad thing.
So far in the UK we've had prosecutions for fraudulent mis-selling of payment protection insurance; fraudulent mis-selling of premium accounts; LIBOR rate fixing; forex rate fixing; and insider trading.
Last month DB settled out of court with traders who alleged - and provided evidence - of precious metal price fixing.
The entire financial industry is rotten to the core. It's the single biggest destroyer of genuine economic growth in the planetary economy, and it also has anti-democratic political influence which operates outside the usual constitutional checks and balances.
There is nothing remotely positive here. The industry needs to die, and it needs to be replaced by completely new structures and institutions that use the profit motive as an excuse for criminality in quite the same psychopathic ways.