Al Qaeda IRA ETA (Euzkadi ta Askasatuna) LTTE (Liberation Tigers of Tamil Elam) etc.

There are numerous groups fighting as non-governmental forces. Modern weapons technology makes it easier for small groups to cause immense damage.

From the last quarter of 2001 the most prominent of these was seen to be Al Qaeda (the Base) founded by Osama bin Laden to fight for a worldwide Islamic state - the Khilafat = Caliphate - with the same principles as the Taliban in Afghanistan or the ruling ideology of Saudi Arabia. People trained by Osama bin Laden are believed to have destroyed the World Trade Center in New York and the Pentagon (11 September 2002); blown up American embassies in Nairobi, Kenya and Dar es Salaam, Tanzania, and blown a hole in a US navy ship in Aden harbor, Yemen. In 2002 the group is believed to have organised or encouraged the attack on Australian tourists by an explosion in Bali, and on Israeli tourists near Mombasa in Kenya. They may also have attacked a French tanker off the coast of Yemen.

Other atrocities were the explosions on the commuter rail system of Madrid, and in the London Underground (7 July 2005). Explosions on the commuter rail system of Mumbai may have been associated with Al Qaeda, or similar groups from Kashmir.

There is a speculation that Al Qaeda may have lured the US into attacking Iraq - which as a secular state was opposed to Osama bin Laden's ideology - by pretending falsely to US interrogators that Saddam had assisted them. (This is from the allegations by "Omar Nasiri" who claims to have been a British and French spy within Al Qaeda. See the BBC Newsnight interview.)

(Other suggestions are that Iran manipulated American politics via an agent claiming to be an Iraqi oppositionist.)

This is a kind of private enterprise army. Whether it has had government support, other than from the Taliban regime in Afghanistan, which allowed it to use bases and training camps, is not publicly known. For example, how much support do its activities in Afghanistan have from official government sources in Pakistan or Saudi Arabia, as opposed to private sources in those and other countries?

Other groups can be found in Ireland (IRA), Angola (UNITA), Sri Lanka (LTTE), Spain (ETA). Together they cause restrictions on travel all over the world, with searches of baggage, lack of litter bins and some useful services, tapping of telephones and electronic communications.

Defence
Can they be countered? In many cases the underlying political problems can be addressed, when the insurgency would die down. Such cases are the demands for independence or local autonomy of such peoples as the Palestinians, Chechen and Tamils in Sri Lanka. In other cases the groups may simply attract psychopaths - people with no moral sense who like to cause explosions. The aims of ETA have been largely achieved, according to the Basque voters who accept the autonomy given them by the Spanish government. But the ETA continue to fight. The IRA, however, have mostly stopped.

UNITA also was given a place in the political process in Angola but resumed the war when the voters didn't elect them as government. That war only ended when their autocratic leader Jonas Savimbi was killed by government troops.

A war in Aceh (Sumatra) may have ended with a political agreement. The war in Sri Lanka also seemed to be about to end with a political agreement in 2002 but then flared up again (2006) and ended with government victory in 2009. (But are the root causes still present?)

Is there any conceivable negotiation that could prevent Al Qaeda's attacks? Here the real problem seems to be within Islam, with the majority of Muslims preferring a peaceful life but a minority of fanatics, full of hate. The centuries of European hegemony replaced a long period of Muslim hegemony in western and central Asia. During that period Islam gradually declined as a culture when the orthodox establishment of preachers suppressed the freedom of enquiry that had existed in the early years. Perhaps what is needed is a new interpretation of the basic texts in a direction that would authorise the modern world of democracy and science. But there are still problems of power. Many, perhaps most, Muslims see their political problems as being associated with the dominance of their region by western power. From the 18th century at least, European powers began to dominate and colonise some of the most important Muslim areas. The British in India conquered and replaced the Mogul Empire. The Russians conquered the historic centres of Central Asia - especially Bukhara and Samarqand. Although these colonial regimes have ended, many Muslims see a cultural hegemony continuing. The 1973 oil crisis saw some rebalancing when the control of the oil price was taken from the western oil companies and given to OPEC.

Is the variety of Islam dominant in Saudi Arabia certain to dominate the whole Islamic world, and therefore promote the idea of extreme puritanism? There are many strands of Islam opposed to the extreme narrowness of interpretation coming from Wahhabism in Saudi Arabia and its analogues in Pakistan (Deobandism). Both these versions reject Sufism, with its promotion of science and reason.

How far is the war in Iraq an example of terrorism? Mainly it has been a national resistance to western invasion, as well as a civil war within Iraq between religious and national groups, and interests from outside such as Iran.