Slowing growth. A stock market in meltdown. And financial turmoil rippling out through the rest of the rest of the global economy.

On the way up, the Shanghai index SHCOMP, -1.28% may not have driven other markets to any great degree, but it is certainly driving them on the way down. Black Monday, even if it has been trending on Twitter, may not be quite the right word for it — the rout in stock markets does not yet compare with the plunge of 1987 or the collapse of the dot-com bubble in 2000.

“ What we can say for certain was that the crash, much like your TV set or your smart phone, came stamped ‘Made in China.’ ”

But this month, we have certainly seen some dramatic falls, and it may well turn out to be the start of a global bear market.

At any one time, one bourse is usually the dominant force in the global markets. It sets the tone, plays out the temper tantrums, and triggers the booms and busts. Once it was the City of the London that led the way. For most of the last century, it has been Wall Street. For a while in the 1980s, it was Tokyo.

After this week, it now looks as if it will be China. If you have any money in equities, you are going to be playing the Shanghai market — because it will dominate everything. And, as they like to say in that country, that is going to make for interesting times.

It is, of course, too early to say whether the markets are going through a fairly standard summer scare — August is very often one of the most volatile months, perhaps because only the interns are manning the trading desks — or if the bull market that started in 2009 has finally come to an end.

By the close of September, the markets may well have recovered their poise, and they may even have resumed their climb toward fresh highs. True, at 76 months, this is already the third longest bull run in history. But the great rally that lasted from 1990 to 2000 ran for an epic 117 months, and the run from 1921 to 1929 ran for 97 months, so there is no particular reason that this one should not have a couple more years left in it. We shall see.

“ Like a bad karaoke singer, Shanghai moved to its own beat, immune to what was happening elsewhere. ”

What we can say for certain was that the crash, much like your TV set or your smart phone, came stamped “Made in China” — and that may prove to be the most significant thing about it.

When the Shanghai index dropped by 8.5% in a single trading session, the pain was immediately felt in every other market in the world. In Europe, the German DAX DAX, +0.97% , French CAC PX1, +0.27% and British FTSE UKX, +0.31% were all off by 7% at one point. On opening, the Dow DJIA, -1.84% lost 1,000 points in the first hour of the day, and even though it recovered later on, it was one of the most volatile sessions of recent times.

And it was all in reaction to what had been happening in China. That is something new.

Despite its rapid growth, China has until now had relatively little impact on the financial markets. Take the first few months of the year, for example. Chinese stocks went on a tear, rising 60% over just a few months. If the Dow were up by 60%, you’d expect every other market to be jumping on that bandwagon. To a lesser extent, the same would be true if the FTSE, DAX or Nikkei NIK, +0.17% were up that much. And yet the Chinese boom had no impact on other bourses, which limped through the first half of 2015 with little sign of life. The same has been true over much of the past decade.

Like a bad karaoke singer, Shanghai moved to its own beat, immune to what was happening elsewhere.

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What academic research there is backs that up. A study published by the Bank of Finland found that the correlation between Shanghai and New York stock prices was rising steadily but had only reached a relatively weak 0.5 by 2010.

It was as if China was — financially at least — a different planet. It was interesting to observe, but it didn’t have much impact on what happened in our world.

In many ways that is surprising. China’s explosive growth has made it the second largest economy in the world. Its stock market, which only started in 1990, was, at least earlier this year, among the most important. By May, the Shanghai Composite was worth $5.9 billion, making it the third biggest bourse in the world, trailing only the New York Stock Exchange, at $20 trillion, and the Nasdaq, at $7 trillion.

With the Shenzhen market worth another $5 trillion, you could argue the combined bourses were the second most important in the world. It is not just about weight of money, important though that is. China is also the crucial driver of global demand, dictating demand, price levels, and growth. It is awash with spare cash, and it has reserve holdings that allow it to dictate terms to the currency markets.

So, in so far as its markets are a forward indicator of the state of the Chinese economy, it makes sense for the global markets to be dictated by them — just as the American economy was once so dominant it made sense to be dictated by the Dow.

The key point about ”Black Monday” is that the Shanghai market is now likely to be the key driver of the global markers — rivalling the NYSE for now, but eventually eclipsing it. It will be volatile, complex, and driven by sentiment and fear more than rational calculation — the Chinese are inveterate gamblers who regard a stock market as a casino minus the neon lights and cocktail waitresses.

And it will be driven by the government far more than any Western bourse has ever been.

But get used to it. If you have any money in any market, from now on you are playing the Shanghai markets — so buckle up. It will be quite a ride.