NATO member countries face asymmetric security threats from national and international terrorism, as the attacks on the United States in 2001, Turkey in 2003, Spain in 2004 and the United Kingdom in 2005 have shown. In addition to these events, authorities in Europe have thwarted at least 19 major terror attacks since 9/111.

In April 1999, the Alliance identified terrorism as one of the risks affecting the security of its members outlined in the Strategic Concept (SC), and a military concept for defence against terrorism was endorsed at the Prague Summit on 21 November 2002. Many of the security challenges faced by the Alliance, however, are still emerging and pose high risks. It may be worthwhile to examine them in more detail, as well as the measures that NATO has adopted since Prague to confront them.

Osama Bin Laden's April 2006 risala ("message") reiterated his strategy of waging a global jihad, calling upon all men, women, and youths to volunteer for suicide attacks and mentioning specifically Afghanistan and Iraq2.

A jihad against the Afghan government and NATO troops can no longer be ruled out in view of several factors. Warlords and tribal leaders continue to be influential and their loyalty towards the regime in Kabul is unclear. Further, the Afghan government's inability to prevent the resurgence of opium as an important commodity has resulted in improved financial resources for terrorists with opium production topping 6,000 tons in 2006, as the United Nations Office on Drugs and Crime has documented. Westner media outlets consistently report that rogue elements of the Pakistani Intelligence Service (ISI) provide logistical support to the Taliban, including training on suicide terrorism. Finally, many al Qaida members are believed to be still at large in the lawless border region between Afghanistan and Pakistan.

Meanwhile, power has been passed from Sunni to Shiá in Iraq for the first time in Arab history. In his 2006 book Radicalization of the Sunni-Shiá Divide, Ely Karmon documented how Iranian Shiá support the Iraqi Shiá agenda across the region through local political groups such as al-Da`waa al-Islamiya in Iraq, Amal in Lebanon, Hizb-I Wahdat in Afghanistan, and Tahrik-I Jafaria in Pakistan. NATO member countries providing troops in Iraq are at risk of being drawn into this polarisation.

Suicide terror attacks are the most deadly form of terrorism, representing just 3% of all terrorist incidents but causing 48% of all terrorism-related fatalities in the period between 1980 and 2003. Such attacks have risen from an average of about three per year in the 1980s to almost fifty a year in 2005. Over 300 suicide attacks in 16 countries - Afghanistan, Chechnya/Russia, China, Indonesia, Iraq, Kashmir/Jammu, Kenya, Morocco, Pakistan, Palestine/Israel, Saudia Arabia, Sri Lanka, Tunisia, Turkey, the United States, and Yemen - have resulted in more than 5,300 people killed and over 10,000 wounded. And as Scott Atran and others have written, 75% of all known suicide bombings in the world have occurred since the September 11 terrorist attacks on the United States3.

We must also remember that such attacks can have powerful economic and environmental consequences even when they take place outside of Europe. In October 2002, a small boat carrying suicide attackers successfully rammed a supertanker, the Limburg, off the coast of Yemen, spilling 90,000 barrels of oil into the Gulf of Aden and causing a brief spike in the price of oil.

In Europe, home-grown terrorism continues to be a security threat to NATO member countries. Unfortunately, suicide terrorism is tolerated, and even admired, on the poorest and least integrated margins of some Muslim communities in Europe. British citizens carried out suicide attacks against the public transport system in London in 2005. Meanwhile, UK security forces foiled assassins planning to deploy ricin, as well as terror attacks on civil aviation. In Germany, police thwarted plans to explode portable bombs on several trains in 2006.

Until now, individuals wanting to engage in terrorist acts in their home country had to travel to the mountainous region along the border of Pakistan and Afghanistan for the necessary training. In the future, a broader choice of training camps may be available to them. Terrorists may learn the basics of road side bombings, vehicle bombs and urban guerrilla warfare in Iraq, and then return home to use that experience to attack destinations in NATO member countries.

In addition, the Preliminary Findings and Recommendations of a December 2006 NATO-Russia Advanced Research Workshop found that a terror attack could use radioactive material to cause an uncontrolled exposure to ionizing radiation4. The objective of deploying a radiological dispersion device (RDD) is the contamination of persons and the environment, causing mass panic rather than mass destruction.

Thousands of potentially suitable radioactive sources are in use at research establishments, medical institutions, industrial facilities, and military sites. Depending on the type of source and radioisotope used, the suitability for a radiological terror attack differs significantly. There are hundreds of incidents of medical and industrial radioactive sources being stolen, abandoned, or lost worldwide every year. In view of the relative ease of constructing an RDD, this increases the probability that terrorists may seek to stage such an attack in a high value target area of a NATO member country.

Terrorists have shown repeatedly both their intent and their partial capability to use weapons of mass destruction (WMD). In Japan, there were incidents of two sarin releases in 1994 and 1995; in the United States, several anthrax releases in 2001; and al Qaida has stated its intent to deploy a nuclear WMD. In the period between 1990 and 2004, at least 27 cases have become known in which nuclear-weapon grade material was successfully diverted5.

Of uppermost importance is the physical protection of the approximately 450 tons of military and civilian separated plutonium. Should terrorists choose the technically easier path of using highly enriched uranium (HEU) for a crude nuclear device, they would only require about 25 kilograms from the more than 1 700 tons of HEU stockpiled worldwide. The exposure of the nuclear black market network engineered by Dr Abdul Qadeer Khan has shown the weakness of international control programmes. The possibility, therefore, of a catastrophic terror attack against a NATO member country with WMD can no longer be dismissed.

The Alliance has demonstrated its resolve to respond to these threats in a variety of ways. For example, in the aftermath of the 9/11 attack, NATO Allies invoked Article 5, the collective defence clause of the Washington Treaty, less than 24 hours after the September 11 attacks. NATO deployed Airborne Warning and Control aircraft in Operation Eagle Assist to the United States on 9 October 2001 and naval forces to the Eastern Mediterranean on 6 October 2001 (formally named Operation Active Endeavour on 26 October 2001). Allies also endorsed an agreed military concept for defence against terrorism at the Prague Summit in 2002.

There remains, however, much progress to be made. Over the next 10 to 15 years NATO member countries will probably face the following threats: globally operating and increasingly lethal terror networks modeled on al Qaida, an increasing number of failed or failing states in Africa and the Middle East, the growing availability of sophisticated conventional weaponry such as surface-to-air missiles, the misuse of emerging technologies as weapons like nanotechnology, the disruption of the flow of vital resources through attacks on the energy supply, and the proliferation of radiological weapons and WMD-whether nuclear, biological, or chemical in nature.

In short, Allied security can be put at risk by rapidly emerging crises in far-away countries because failed states have proven to be hospitable environments for the terrorists who threaten us at home. The traditional and pre-planned military solutions of the Cold War, therefore, are no longer suitable. Fortunately, recent NATO Summits have adopted incremental measures to enhance Allied capabilities to fight terrorism. Since 2004, a specific initiative known as the "Defence Against Terrorism Programme of Work", launched under the Conference of National Armaments Directors, has aimed at the coordinated development of cutting-edge technologies to counter terrorist threats. Prospective measures, among others, include countering car and road-side bombs, reducing the vulnerability of aircraft to man-portable air defence missiles and the vulnerability of helicopters to rocket-propelled grenades, and protecting harbours and ships from explosive-packed speedboats and underwater divers.

In addition, Allies now have a fully operational NATO Response Force (NRF) at their disposal. The NRF will serve as a catalyst for transformation and interoperability, and by doing so will enhance the quality of Allied armed forces whether they be used for NATO, EU, UN or national operations. At Riga, member countries expressed their support for mechanisms to ensure long-term force generation and to allow for a more sustainable and transparent approach to maintain the Force's future capabilities. While neither the NRF nor the recently-approved Special Operations Forces Transformation Initiative are intended to be used exclusively for counter-terrorism purposes, they enhance the Alliance's ability to mount expeditionary operations. This capability, in turn, will invariably prove useful in confronting threats that originate within failed states.

NATO countries have also responded diplomatically. The Euro-Atlantic Partnership Council's Partnership Action Plan against Terrorism, launched at Prague, is updated annually. The Alliance set another important milestone at the November 2006 Riga Summit by endorsing a Comprehensive Political Guidance that highlights the threats posed by terrorism and the spread of weapons of mass destruction, among others.

At the Riga Summit, NATO countries emphasised that collective defence remains a core purpose of the Alliance. For the foreseeable future, global terrorism will remain the greatest threat to transatlantic defence. European members of the Alliance have already experienced a wide spectrum of security-relevant events besides the terror attacks in Turkey, Spain, the United Kingdom and Germany.

Outside Europe, arrests in Toronto in 2006 could be indicative of closer coordination and possibly cooperation between terrorist sleeper cells in North America. In Afghanistan, suicide bomb attacks and improvised explosive devices have become increasingly the attack mode of choice for insurgents allied with the Taliban. If successful, these attacks could facilitate the return of al Qaida. And in Iraq, terrorists are increasingly engaging US-led coalition forces in frequent attacks using a wide variety of improvised explosive devices whose destructiveness could well be imported into NATO countries themselves.

Future terror attacks may originate either within the boundaries of NATO member countries due to home-grown terrorists or from outside the Euro-Atlantic area. Such attacks may occur with little if any notice, involve unconventional forms of armed assault, and entail the use of asymmetric means, and even WMD. Fortunately, strengthening the Alliance's ability to meet the challenge of asymmetric threats is one of NATO's top priorities.