The terrorist attacks of Sept. 11, 2001 in New York and Washington raised a tricky foreign policy challenge for Europe when it came to supporting the US-led "coalition of the willing" in Iraq and its war on terror. Domestic security became a central concern for governments across Europe and a number of elections were fought on its back. Terrorist attacks in Madrid and London fueled those worries.

At the same time, the rush to beef up defenses and toughen anti-terrorism laws has been accompanied by the intertwined fears of terrorism and immigration. Home to sizeable Muslim populations, western European nations are grappling with integrating those groups, accommoding Islam as well as weeding out the problem of homegrown Islamist terror.

As the continent frets over how far civil liberty should be sacrificed for security and where to draw the line between curbing extremism and fostering diversity, DW-WORLD.DE takes a look at what's changed in Denmark, France, Italy and The Netherlands in the five years since the Sept 11 attacks.