It's salient to note that the most severe global financial crisis ever has not brought about significant innovation in ideas or in actions. It's likely that the effects will not last as long as the Great Depression, for a couple of reasons - both related to lessons learnt from the 1929 crash.
First, international response has centred around large-scale Keynesian increases in public spending, to counter the widespread retreat of private capital. Second, the Depression was prolonged by trade protectionist policies, which isolationism is not being practiced today to any great degree.
But the world's leaders and policy-influencers are too busy reacting to the crisis to re-think their approach to financial systems. Certainly, there is a long-overdue recognition of the need to return to diligent regulation and monitoring of financial markets. It's quite plausible that financial regulation will become tougher than ever - which will make capitalists squeal, as not only is regulation anathema to "free" markets, but it also imposes transaction costs. Yet at the very minimum, regulation should force a far greater transparency to the financial instruments that are traded - which is one of the roots of the crisis: that is, trade in little-understood financial instruments into which were wrapped toxic unsustainable "low-doc" housing loans.
"If you don't fully understand an instrument, don't buy it" - Emilio Botin, chairman of Santander, Spain's largest lender.
But that is typically abrogated by the philosophy that
"If you look for high profits, you have to face higher risk".
Botin clearly didn't follow his own advice. The trouble is, if "everyone is doing it", the risk doesn't seem so great - it's spread around. That's one of the reasons Bernard Madoff got away with the largest financial fraud in history (just the same old pyramid - or Ponzi - scheme where dividends were paid from capital, not from investments, and more and more people were sucked in). Nobody understood how his instruments could make money, but the return was good and Madoff was "reputable". Financial regulation has to go far enough so as to prove or disprove any such scheme before the size gets into the tens of millions, let alone billions.
In the end, risks that were spread around were so great that they spread globally.
Last but most importantly, a very large opportunity has been missed - so far - by governments around the world. In attempting to revive capital formations with large injections of government money, it is the ideal time to foster - force - change in investment patterns to greatly favour lower carbon emissions. Instead, the financial crisis looks to be derailing the cause of remission of global warming in the crucial years in which the environmental crisis is now fully admitted.