Few pedestrians noticed a driverless, rickety wagon pulled by an old bay mare near the financial district's busiest corner. The horse paused outside the offices of J.P. Morgan & Co.

Suddenly, a puff of smoke, a flash and a "crash out of a blue sky," as one account put it. An automobile was hurled into the air, plate glass windows shattered for blocks, grotesquely wounded people writhed on the pavement. Others were reduced to "lifeless lumps of clay."

The ramshackle wagon held 100 pounds of dynamite packed with 500 pounds of fragmented steel window sashes. A remote control device detonated the load, driving thousands of jagged metal shards outward into the crowded sidewalks and streets. In an instant, 40 people were dead or dying. Nearly 300 others were injured.

Soon, word spread that another bomb was set to explode, causing "a mad panic in which men ruthlessly trampled women in an effort to escape," a reporter wrote.

It was Sept. 16, 1920. It was neither the first act of terror on American soil, nor the last.

But the Wall Street bombing was different from previous attacks. The indiscriminate malevolence was a departure from earlier attacks that were more narrowly targeted.

"There was no objective except general terrorism," The St. Louis Post-Dispatch observed. "The bomb was not directed against any particular person or property. It was directed against a public, anyone who happened to be near."

"It was the equivalent of a Timothy McVeigh attack, a horse-drawn carriage [driven] up to a target," said Larry Taulbee, an Emory University political science professor who advised a committee studying security for the Olympics. "They're looking for absolute shock value. By attacking civilians, you're trying to generate fear. Things haven't changed much."

The 1920 bombing stunned an already jittery American public that had come through a world war and a flu pandemic and was wracked by fears of labor riots, Bolshevik infiltrators and bomb-throwing anarchists.

Fear and uncertainty

In contrast, the Sept. 11 attack rocked a nation coming off a decade of great prosperity, unprecedented communications technology and increased self-absorption. Suddenly, the illusion of safety at home vanished.

"The targets have tended to remain constant," said Harvey Klehr, an Emory University history professor who has studied American radicalism. "The biggest difference is the scale.

"Most ordinary citizens feel more afraid today than they did then, partly because of the role of television. Also, the weapons available then weren't of the same kind of scope. Now we're talking about biological weapons, nuclear weapons, planes slamming into buildings."

Still, that earlier era in many ways resembles the current emotional landscape of gnawing fear and uncertainty, where it seems that some new calamity is set to happen. As it has today, that fear led to roundups of certain immigrant groups, an expansion of federal law enforcement powers and ultimately, a tightening of immigration law.

"You have a period in the Red Scare where the nation is scared and everything seems like it's falling apart," said Leo Robert Klein, a librarian at the William and Anita Newman Library at Baruch College, CUNY, who compiled history for a Web site on the Red Scare of 1918 to 1921. "People were expecting to be blown up. It wasn't like everyone woke up and decided to be hysterical. It was a buildup of several events."

Anarchist attacks weren't new to Americans. Eight Chicago police officers were killed in 1886 by a bomb; President William McKinley was shot to death in 1901; a bomb at the Los Angeles Times offices in 1910 killed 20; and in 1919, a series of bombs was mailed to business and government leaders.

"Radicalism has gotten a foothold," warned an Atlanta Constitution editorial after the 1920 bombing. Lawlessness, anarchy and terror are "the problems that confront the upright, upstanding citizenry of this country today as at no other hour before in our nation's history."

Each generation thinks its problems are unique, but history has a way of recycling itself.

The Washington Post labeled the Wall Street bombing an "act of war."

But then, like now, America was not sure who exactly it should fight.

No charges ever filed

Anarchists, especially Eastern European and Sicilian immigrants, were suspected in the attack. They were portrayed as "bearded, crazed bomb-wielding people," said Klein.

"A great deal of public fear focused on immigrants," said Klehr. "There was a fear of foreign sponsorship by the Soviet Union."

Investigators believed they had promising leads found at the scene in a well-worn harness and severed hoofs with metal shoes with blacksmith shop lettering. Sounding like President Bush vowing to "smoke out" Osama bin Laden, a 1920 bombing in The Atlanta Journal trumpeted: "Perpetrators of Wall Street Blast Will Be Caught, Expert is Confident."

The expert was wrong: No one was ever charged in the bombing.

The mail bombings of 1919 spurred U.S. Attorney General A. Mitchell Palmer to order what are now known as the Palmer Raids, a gigantic human dragnet of immigrants and leftists.

"As a foe, the anarchist is fearless of his own life, for his creed is a fanaticism that admits no respect of any other creed," Palmer said in 1920. Palmer had a personal incentive in the effort. One of the mailbombs a year earlier exploded outside his home.

Today, Attorney General John Ashcroft is overseeing an immigrant roundup the likes of which has not been seen for generations. The Bush administration has declared it intends to try terrorism suspects before military tribunals, which can keep secret evidence from defendants and convict suspects and impose the death penalty with only a two-thirds vote.

To ease fears of a pending market crash, Wall Street reopened the next day, confidently saying it would conduct "business as usual." Shattered windows were replaced by cheesecloth as traders performed their duties.

"The explosion solidified national support behind Wall Street, transforming the daily routine of finance into an act of defiance and patriotic affirmation," said Beverly Gage, a fellow at Columbia University who is writing a book about the 1920 bombing.

Today, buying stock, riding airliners and even engaging in conspicuous consumption are all seen as patriotic acts.

As they do now, Americans in 1920 lived with the specter of an impending attack.

The Atlanta Journal's banner 1920 bombing Sept. 20, 1920, warned:

POST CARD WARNING SAYS N.Y. CUSTOMS HOUSE WILL BE BLOWN UP DURING TUESDAY AFTERNOON

The next day's 1920 bombing was:

N.Y. CUSTOMS HOUSE BLAST FAILS TO MATERIALIZE

A front-page Atlanta Constitution 1920 bombing on Oct. 30, 2001, accompanied by a photoss of Ashcroft, warned:

Terrorists may strike this week, no details

Later, Americans held their breath when there were warnings that West Coast bridges might be bombed. Still, the other shoe didn't drop.

The Red Scare of 1991-1920, finally burned itself out. "There was a return to normalcy in the 1920s," Klehr said. "Today, we have a different form of terrorism. This is religiously based, that changes the equation. I think this will be more long lasting."

Still, there are lessons that can be learned from tumult of other eras.

"It was an extreme moment in U.S. history," said Klein. "But it turns out it wasn't the end of the world after all."