Terrorists - All
Terrorism - "An organized system of intimidation, especially for political ends". (Chambers English Dictionary)
Unfortunately terrorism has always been with us, one particular and yet not uncommon form is "government by terrorism "(Chambers Dictionary)
Beginning with the letter A, we have the Assyrians in the seventh century BC. Their kings Ashurbanipal, Sargon and Sennachharib who "came down like the wolf on the fold" (Byron) devastated Egypt and Mesapotamia riding their horse drawn chariots. Democratic Athens was no different punishing their renegade allies who were themselves Greeks in the 5th Century BC.
The Romans establishing their empire began by destroying rival Carthage with the cry "Carthago delenda est -" Carthage shall be destroyed. They themselves in subsequent centuries suffered from Marauders, Attila and the Huns in 430-450 AD, a name so engraved in memory that the Allies in 1914 -1 918 referred to the Germans as Huns.
The European "Dark Ages" saw the Wandering of the Tribes", Goths, Lombards and Vandals, hence Vandalism.
The 11 th century saw the Mongols, perhaps the ultimate terrorists, from Central Asia under Genghis Khan on their little horses laying waste everything in their way. In the 13th Century Mohammed of Ghazni from Central Asia also delighted in making mountains of human skulls in NW India. Over the centuries Europe settled down and apart from internicine war made steady progress. But in the 18th century, France perhaps the most cultured of the European nations staged their "Reign of Terror" which paradoxically prefaced "Liberty, Equality and Fraternity". Elsewhere, in the world colonizing conquerors have practised terrorism. In the 16th century de Azevedo, the Portuguese Captain General in Colombo, also known as the King of Malwana is said to have impailed infants on his bayonets.
Nearer to our times British Governor Maitland suppressing the Uva rebellion of 1848 ordered that no living plant or animal should survive resulting in the permanent desolation of once so fertile Velassa (a lakh of fields)
I cannot finish this list without mentioning the American bombing of Hiroshima and Nagasaki when defeated Japan on their knees was already willing to surrender, and last but not least President Bush’s "War on Terror" in Iraq, following Al Qaida and 9/11.
One can see two instances in this short list, of terror arising within a community as happened in Athens and its Greek colonies and in France’s Reign of Terror. All others are examples of Terror from external agents, conquerors and colonizers. A feature of the 20th Century seems to be a reversal of this tendency, whereby terror is internally derived. We see instances in Africa, the Mau Mau in Kenya; in South America the "Shining Path" in Peru; and in Asia the Khmer Rouge in Cambodia and the Liberation Tamil Tigers of Eelam.
My intention in setting down this list from times past and many lands, which indeed could be much longer, is to show that terrorism as defined above has many causes and arises from varied circumstances and should not be put in one basket., such as a "War on Terror". The counter would be to treat the cause or causes and not to attempt to crush its head. Ms Hillary Clinton and Barak Obama quite clearly have recognized this, unlike George Bush whom one could call a perpetrator.