Having talked for many weeks about nothing other than faltering share prices, febrile consumer confidence and the likelihood of recession, Wall Street financiers had their woes put into stark perspective by the terrorist attack on the World Trade Center’s twin towers in New York.
Suddenly, worries about equity values, industrial output and rising unemployment became utterly futile.
For those with friends, colleagues and rivals in the Trade Center complex, the only concern was for human life.
Who was in there? Have they been in touch? Did they get out?
Old rivalries were immediately set aside, as blue-chip investment houses rallied round to help those whose staff were trapped inside the doomed buildings.
Worst hit was Morgan Stanley, one of Wall Street’s premier league firms, which occupied 50 of one of the tower’s 110 floors. Its London spokesman was too shocked to issue a formal statement.
Recession threat
With world markets so nervous about economic prospects, this atrocity can only make matters worse.
In recent months, the American economy has been dragged along by dogged US consumer optimism, even though many companies have been slashing investment and laying off workers.
It is inconceivable that American consumer confidence will not be adversely affected by this outrage.
From here, the threat of recession looms large.
Oil prices
Within minutes of television pictures of the suicide attack reaching traders’ desks, oil prices began to rise sharply.
Many oil brokers believe tension in the Middle East will inevitably escalate, leading possibly to a short-term energy crisis.
However, Opec, the organisation of leading oil producing countries, insists that it will “turn on the taps” to make sure the world economy is not thrown into chaos by fuel shortages.
That gesture will be hugely appreciated by Japan, one of the world’s top three economies, which imports every drop of oil it consumes.
Japan has been mired in recession for longer than most analysts care to remember.
The Tokyo stock market index, which reached 39,000 in 1989, has now fallen below 10,000 points.
America is Japan’s most important export market, so when US consumers are frightened, workers all over Japan feel the squeeze.
The scale of the discomfort felt by financial markets was reflected by the extent to which gold prices leapt sharply, up by as much as $16 to $289 an ounce in London trading.
Not since the early 1980s has gold been in such instant favour.
Many investors had long written off the precious metal as a safe haven in times of crisis, but few have ever witnessed a shock to match this one.
Human spirit
It’s impossible to say when American financial markets will re-open. It’s not just a question of fixing trading systems but of human spirit.
With so many Wall Street employees having lost their lives, few feel it would be appropriate to begin dealing again before bereaved families have had a chance to absorb the full horror of Tuesday’s terrible events.
With so many people working in downtown New York, it could be many days before the full death toll is known.
Elsewhere, stock markets reacted with a mixture of fear and bewilderment.
In London, where the Stock Exchange was evacuated as a precaution, shares dropped precipitously on the day of the attack, closing 287 points down, a fall of nearly 6%. Other European bourses slumped in tandem.
The suicide pilots struck not only at innocent civilians, but at the heart of what has been buoying America’s struggling economy: the innate confidence of the country’s people.
By undermining that, the terrorists hope to destroy much more than one of the world’s tallest buildings. They want to bring down the Western world’s financial system.
In the short-run, these killers may damage prosperity in the US and beyond, but in the long-run world leaders are determined to face them down.
Wall Street, New York and America will bounce back from this carnage.
BBC’s business editor Jeff Randall