The killing of a policeman in a terror attack has heightened tensions as France chooses its next president.
Their policies on Syria, Russia, terrorism and the European Union.
Terrorism laws contain extra hurdles to secure a conviction, so prosecutors and police may prefer to charge offenders with murder or assault in some cases.
Violent dissident republicanism is still making its presence felt.
From the Islamic State to North Caucasian rebels and far-right nationalists, Russia is facing overlapping extremist threats.
All around us in Western media, young Arabic-looking men with beards equal terrorists. But maybe they're just hipsters.
The Nigerian government has dealt Boko Haram some serious blows, but the insurgency is far from over.
In the aftermath of Westminster, how much reporting was constructive and how much was simply publicity for terrorists?
The Astronomer Royal answers some of the world's – and the universe's – biggest questions.
We naturally overestimate the risk of rare events, like shark attacks or terrorism. But there are things you can do to think more rationally about the real risk.
Al-Qaeda and Islamic State have both encouraged would-be terrorists to use cars and trucks as weapons.
A charity is recommending the public be advised to help each other in emergency situations.
A way in for government would also allow hackers access.
Last week’s terrorist attack in London reveals the challenges facing European intelligence and security services in preventing people who use everyday things like cars to cause mayhem.
For all their defiant talk of 'business as usual', savvy leaders know that any good response to a crisis is also an emotional performance.
Motivation is what separates an act of violence from an act of terrorism, and we don't know what drove Khalid Masood to kill.
A survey of what young people perceive to be the biggest threat to Europe reveals some surprising information.
Hyperbolic approaches to threat measurement don’t lead to very effective counter-terrorism policy.
Was the London attacker acting alone? Was he really a soldier of the Islamic State? Research on the nature of jihadism in the West reveals possible answers.
The ban on electronic devices in cabin luggage overlooks the airports that would be least likely to detect a bomb.