The New York Stock Exchange is to reopen this morning as the city struggles to get back to business following the devastation of the financial area.
The world will be watching with deepening anxiety for any signs of a loss of confidence in the US markets, where $100 billion-worth of trades are conducted daily, $43 billion in the New York Stock Exchange alone.
The probability of recession in the US has inevitably increased, with airline companies heading a list of business sectors reporting huge losses from the nationwide travel paralysis and its aftermath.
Vice-President Dick Cheney has said, however, that he expects a rebound at the end of the year. The depth of the psychological impact on Wall Street has yet to be fully appreciated.
Despite intense competition, the financial world is close-knit and almost everyone will know some of the victims among the 40,000 brokers, traders and analysts who worked in the twin towers.
The toll of missing from the catastrophe rose yesterday to 5,097 as more complete lists were compiled from relatives, New York Mayor Rudolph Giuliani told reporters.
However, only 180 bodies have been found and 115 identified. Masses were held in St Patrick's Cathedral and other churches for the victims of the attack, which practically wiped out major financial firms such as Cantor Fitzgerald, which lost all 750 employees in the trade centre.
Mr Giuliani said he was getting inspiration from Winston Churchill's speeches in a book called Five Days in London, about how British people survived the Nazi bombing of 1941 and 1942.
He urged those from outside who wanted to help New York to "come here and spend money, go to a restaurant and a play - you might even get tickets for The Producers," a reference to Broadway's most popular show.
Wall Street also faces the huge logistical obstacles of coping with the return of most of the 180,000 people employed in the financial sector.
Suction trucks were yesterday trying to remove dust, soot and debris from roads, but window ledges and roofs are still deep in the choking debris which showered down all across southern Manhattan.
In a tribute to the heroic efforts of over 300 firemen and scores of other rescue workers who perished, the opening bell at the Stock Exchange at 9.30 a.m. will be rung by representatives from the Police and Fire departments, Emergency Medical Services and Port Authority of New York and New Jersey.
Wall Street, like the rest of the city, is showing its defiance by displaying the Stars and Stripes, including a huge flag draped by construction workers using a crane over the six pillars of the stock exchange entrance.
NYSE chairman Richard Grasso said the exchange would observe two minutes of silence for the victims before the start of trading and that those on the exchange floor would join in singing God Bless America.
The markets were closed for four days after two hijacked jetliners destroyed the World Trade Centre and forced the shutdown of nearby Wall Street for four working days, the longest shutdown in almost a century.
Mr Grasso said computer and communications systems had been tested successfully and "based on today's evaluation of our systems, at 9:30 Monday morning trading will resume".
The electronically based Nasdaq, five blocks from the trade centre, will also resume normal trading.
While Mr Grasso predicted that trading would be without constraints and orderly, there are concerns about a collapse of the market after the opening bell. The Securities and Exchange Commission has eased rules governing stock buybacks by companies to maintain stock values.
Many companies, including Cisco Systems, are expected to repurchase their stock as a signal of their confidence in the market and the country.
The American Stock Exchange near the twin towers is so badly damaged that its operations are expected to be temporarily moved to the NYSE and other regional markets.
About $100 billion-worth of trades are conducted every day in the US, bringing the estimated losses from the shutdown to $400 billion.
These will be compounded by companies such as General Electric, Ford, and Delta, which issued profit warnings on Friday linked to the devastation.
Wall Street money managers have warned that large corporations, crippled by shutdowns, the inability to move goods and services, and payouts by insurance companies, were facing unplanned costs of billions of dollars.
Insurance and travel-related companies, including airlines, hotel chains and airlines, are the worst hit.