The World Trade Center burns after being hit by planes in New York Sept. 11, 2001.
Reuters/Sara K. Schwittek
An unprecedented onslaught from the US hasn't destroyed the terrorist organization. What is the secret of its resilience?
The attacks in Manchester and London can be categorized as ‘newest’ terrorism, which is more lethal and public than previous forms of terrorism.
The latest wave of terrorism aims to kill as many people as possible, as horrifically as possible, with new tools and methods. That makes fighting back more difficult.
When it comes to Islamist extremism and terrorism, change is a constant.
Iraqi special forces soldier advancing toward Mosul, Iraq.
AP Photo/Khalid Mohammed
What happens to the Islamic State if it loses the battle for territory in Iraq and Syria? Here's a list of ways it might go down.
The heavy truck that was driven into a crowd at high speed killing scores on Bastille Day in Nice.
The Bastille Day attack in Nice – committed by an individual unknown to French security services – marks the evolution of radicalisation in many ways.
Brussels remains on high alert as raids continue.
Christophe Petit Tesson/EPA
The road to radicalisation can morph from an idea about noble deeds.
Leighton Walter Killé/TCF
Social media were at the heart of the attacks in Paris, serving as tools of communication and also sources of information and emotion.
The British government's position is that this was a legitimate act of self-defence in a war zone. But there are other issues to examine.
Don’t believe the hype.
Life in the caliphate wasn't exactly as advertised for one group of former fighters.
Moroccan woman Samira Yerou is arrested at Barcelona airport in March on suspicion of attempting to join IS militants in Syria.
REUTERS/Spanish Interior Ministry/Handout via Reuters
Western media tropes of black widows, deviant sexuality and unthinking compliance fail to explain why violence crosses the gender divide.
The scene in Zaria.
A week of carnage across northern Nigeria proves Boko Haram is alive and well. Can the Nigerian army get its act together?
Attacks in France, Kuwait and Tunisia come against a backdrop of increasing extremist violence across the world.
Women hold pictures of their family members following the massacre.
The Camp Speicher massacre was one of Islamic State's earliest and worst mass killings – but it was nearly buried under a tide of misinterpretation and denial.
Destruction from an early battle between IS and Iraqi forces in July 2014.
By exploiting weaknesses and divisions, the extremist group has been able to establish a brutal regime in just 12 months.
Kadiza Sultana, Amira Abase and Shamima Begum left the UK in mid-February.
Record numbers of arrests of young Britons on suspicion of terrorism offences shows the need for a new and effective approach to online jihad.
Under the leadership of both Ayman al-Zawahiri and Osama bin Laden, al-Qaeda has failed to reproduce an event that has shaken the international order since 9/11.
Islamic State's rapid successes in Syria and Iraq stand in stark contrast to al-Qaeda's efforts at global jihad over the past decade.
Resisting division in Denmark.
A memorial service has been held in Copenhagen for the victims of the shootings that killed two and injured five in the city on February 14. A crowd of up to 40,000 people gathered just around the corner…
Wish you were here?
What makes someone want to travel to some of the most dangerous places on earth to fight alongside terrorists? It’s a question we’ve been asking about young people for more than a decade. But the rise…
Security conscious. Behind Boris Johnson’s analysis of terror.
BackBoris2012 Campaign Team
Last week, London’s mayor Boris Johnson generated a largely negative reaction when he described European jihadis as “wankers” – people who feel they are failures and that the world is against them. Now…
Belgian security forces patrol near the Jewish museum in Brussels.
Even as the world was still trying to make sense of the Paris attacks, attention suddenly shifted towards Brussels with the news that two suspected jihadis had been killed in a police anti-terror raid…