Four years ago, Lehman Brothers fell, sending shock waves through the financial system.
Credit and lending dried up, many major financial institutions looked vulnerable, and the world economy slipped into a crisis from which it has not yet recovered.
Indeed, the fire-fighting that was needed at that time led to a stressing of government balance sheets and build-up of debt that is the root cause of the second dip of what many now call the Great Recession.
Over these four years, too, the reasons for the crisis have been deconstructed and analysed near-endlessly.
Some of them -- poor regulation, irresponsibility in the financial sector, a lack of understanding of macro-prudential risk -- are now generally accepted as primary causes.
It seems important to ask, therefore, whether these lessons learnt have caused reforms to be implemented.
The answer, unfortunately, seems to be no.
Indeed, the fact is that too little has changed since Lehman fell.
Consider the questions of regulatory reform.
Any hope of closer co-ordination between regulators internationally foundered on the desire of some countries to protect their competitive advantage in lax regulation.
Even within individual countries, the lessons have not been applied.
Regulators dealing with dynamic financial markets cannot always be tied down by legislated rules that are quickly out of date.
Principles-based regulation does a lot better than rules-based legislation.
Yet in the United States' landmark legislative response, the Dodd-Frank Act, started with 'only' 848 pages, has now exploded, with its rules, into being nearly 9,000 pages.
Then there's the question of regulatory co-ordination, necessary to stop financial firms from shopping around for the most lax regime.
The Sahara case in India demonstrates that regulators in this country -- the Securities and Exchange Board of India, the Reserve Bank of India and the corporate affairs ministry -- barely even talk to each other except at the highest levels.
The dynamic between the state and financial markets has actually changed very little. States stepped in to bail out stressed financial firms and entire systems in the aftermath of Lehman's fall, expanding public debt dangerously.
Yet the European Union, for example, can legitimately complain that this has not bought it respite from financial markets -- which immediately turned around to try and make money off the fact that government bond yields were diverging and increasing in consequence, precipitating the euro crisis.
Further, given that public finances were key to recovery after Lehman, there was a wide consensus that plugging loopholes in tax collections and going after tax havens was a global necessity.
Yet in India, as the outcry about the General Anti-Avoidance Rules, or GAAR, and the persistence of the "Mauritius route" have shown, financial markets have fought back against that consensus.
Meanwhile, the state's big monetary interventions -- of which the Federal Reserve's various giant expansions are examples -- have had little enough effect on unemployment or bond yields, and have served only to prop up financial sector balance sheets and stock market indices, and drive up commodity prices -- sending India, in particular, deeply into crisis.
The recovery has been expensive, and has disproportionately benefited those who got the world into crisis in the first place.
Worst of all, attention has drifted away from the perverse incentives and short-term thinking in the financial sector that was the biggest cause of the problem.
Those remain completely intact.
Four years after Lehman fell, its clones go from strength to strength.