And there was another parallel with U.S. experience: as credit boomed, much of it came not from banks but from an unsupervised, unprotected shadow banking system. There were huge differences in detail: shadow banking American style tended to involve prestigious Wall Street firms and complex financial instruments, while the Chinese version tends to run through underground banks and even pawnshops. Yet the consequences were similar: in China as in America a few years ago, the financial system may be much more vulnerable than data on conventional banking reveal.

Now the bubble is visibly bursting. How much damage will it do to the Chinese economy — and the world?

Some commentators say not to worry, that China has strong, smart leaders who will do whatever is necessary to cope with a downturn. Implied though not often stated is the thought that China can do what it takes because it doesn’t have to worry about democratic niceties.

To me, however, these sound like famous last words. After all, I remember very well getting similar assurances about Japan in the 1980s, where the brilliant bureaucrats at the Ministry of Finance supposedly had everything under control. And later, there were assurances that America would never, ever, repeat the mistakes that led to Japan’s lost decade — when we are, in reality, doing even worse than Japan did.

For what it’s worth, statements about economic policy from Chinese officials don’t strike me as being especially clear-headed. In particular, the way China has been lashing out at foreigners — among other things, imposing a punitive tariff on imports of U.S.-made autos that will do nothing to help its economy but will help poison trade relations — does not sound like a mature government that knows what it’s doing.

And anecdotal evidence suggests that while China’s government may not be constrained by rule of law, it is constrained by pervasive corruption, which means that what actually happens at the local level may bear little resemblance to what is ordered in Beijing.

I hope that I’m being needlessly alarmist here. But it’s impossible not to be worried: China’s story just sounds too much like the crack-ups we’ve already seen elsewhere. And a world economy already suffering from the mess in Europe really, really doesn’t need a new epicenter of crisis.