"Ironically" you could make an argument that 9/11 helped caused the financial crisis. If you remember, right before 9/11 was the Enron scandal and others started popping up so lots of resources were headed into investigating those companies including with prison sentences. Then 9/11. The FBI and DOJ basically left skeleton teams on financial issues, shuffled a bunch of it off to the SEC (which is not a prosecuting body) and went all in on TERRORISM. I know it wasn't part of the crisis, but one reason people couldn't get anyone to care about Madoff is resources for an investigation like that were limited to terrorism cases, so it had to collapse so that the evidence was just sitting there.
And it was the same way in many of the countries across the world, the shift in agency resources. The LIBOR manipulation eventually managed to get tied near a terrorism case and that's how some of the agencies grabbed more resources to tackle that.
Amusingly, the US government's response from an administrative perspective to both 9/11 and the financial crisis was almost exactly the same dusted off idea. Shuffle agencies and departments around and place them into new entities with questionable oversight, lines of authority and powers: DHS and CFPB are almost carbon copy entities from an APA perspective. Neither one satisfies anyone.
