Sadly the planting of bombs to kill and maim innocent civilians isn’t a new form of political extremism.

Last Monday, Patriot’s Day, two bombs exploded near the finish line of the annual Boston Marathon, killing three and sending over 170 to the hospital, 17 of them with critical injuries. The explosive devices were reported to be pressure cookers, stuffed with metal ball bearings and detonated by batteries, electronic circuitry and a remote device.

Security surveillance videos led the FBI to identify as prime suspects two brothers, Tamerlan and Dzhokhar Tsarnaev, aged 26 and 19, ethnic Chechnyans who have lived in the U.S. for over a decade. A massive manhunt ensued. Thursday night, following a car chase and fierce firefight, Tamerlan was fatally shot by police, and Friday night Dzhokhar was found hiding in a boat parked beside a Watertown home and taken into custody.

The Boston Marathon explosions, a short distance from Copley Square, took place nearly 127 years after an infamous bomb blast occurred in another square in another large American city.

On May 4, 1886 in Chicago’s Haymarket Square, an unknown person threw a bomb at policemen who had been sent to disperse a peaceful labor rally in support of workers striking for an eight-hour day. Seven police officers and four civilians were killed and many others injured. In the highly controversial trial that followed, eight anarchists were convicted of plotting the bomb attack and four of them hanged.

Fringe members of the anarchist movement were the violent political extremists of late 19th and early 20th-century Europe and America. They repeatedly set off bombs in an attempt to foment revolution, overthrow established political authority and create a socialist economy, and the very mention of their name sent chills up the spines of polite society. Their most infamous acts were the bombing assassination of Russian Czar Nicholas II in 1881 in St. Petersburg and the detonation of bombs mailed to public officials (including Attorney General A. Mitchell Palmer) in eight different U.S. cities in 1919.

The Haymarket Square episode did not spark a revolution. In fact, it represented a major setback for burgeoning labor unions, which were struggling to gain political traction and public acceptance. Likewise, the assassination of Nicholas II unleashed a wave of repression that stalled political reform in Russia for a generation, and the 1919 U.S. bombings led to the Red Scare, involving the indiscriminate arrest and deportation of hundreds of suspected foreign-born radicals and anarchists.

Authorities don’t yet know the motives of the Tsarnaevs or whether they were part of a larger conspiracy. But the sophistication of the explosive devices they employed and the suspects’ roots in the Chechnyan region of southern Russia, the site of separatist and militant Islamic insurgency since the 1990s, suggest links to, or at least strong sympathies with, a foreign extremist group.

Angry, violent, mentally unbalanced loners seem to prefer assault rifles to bombs. Perhaps it’s the instant gratification of being able to view their handiwork at close range as their victims cringe with fear, crumple to the ground or cry for help.

Building, planting and detonating a bomb, however, not only requires more technical skill than using a firearm, but takes more planning, patience and restraint, particularly if the perpetrators intend to escape.

In addition, bombers, unlike solitary gunmen, usually want to make a powerful political statement and tend to work in concert with those of like mind. Timothy McVeigh, for instance, who cratered the Federal Building in Oklahoma City in 1995, was a disgruntled Gulf War veteran and American militia movement sympathizer. McVeigh harbored a virulent hatred of the federal government and was angered by the FBI’s handling of the Waco Siege and Ruby Ridge incidents. He had the active help of one accomplice and at least the acquiescence of others.

Al-Qaeda and its affiliates have made passenger airline bombs, truck bombs, IEDs and suicide bombs their signature weapons for dramatizing the political message that the U.S. and other Western powers are impotent to stop the spread of their radical, muscular version of resurgent Islam.

It’s not that extremists trying to make a political statement with explosives don’t have legitimate grievances. For the anarchists, it was the exploitation of labor in industrialized society and the political repression of established governments. For Timothy McVeigh, it was the overreaching of federal authorities. For al-Qaeda, it was Great Power hegemony in the Islamic world, especially the Middle East, in league with corrupt, authoritarian local rulers. For Chechnyans and other insurgents in the Caucasus, it’s been Moscow’s use of brute force to retain control of that ethnically diverse region.

It’s just that bomb attacks against civilians are as inhumane as the injustices they seek to redress. As a result, they alienate public sympathy and summon the full resources of governments to crush those responsible for the attacks.

If history is any guide, whatever political statement the Boston Marathon bombers intended to make will have just the opposite effect – turning the American people against whatever cause inspired their attack and redoubling their resolve to resist such aggression.

The violent political extremists of today will continue to find, as did those of yester-year, that they achieve nothing by slaughtering innocents, other than to bring about their own demise and discredit their cause.

Elliott L. Epstein,a local attorney, is founder of Museum L-Aand an adjunct history instructor at Central Maine Community College. He is the author of “Lucifer’s Child,”a recently published book about the 1984 oven-death murder of Angela Palmer.Hemay be reached [email protected].