Two American writers chime in along similar lines.

Brian Fishman, on WoTR concludes:
Terrorism is not just propaganda of the deed, it is a press release written in blood
Link:http://warontherocks.com/2015/01/jih.../?singlepage=1

Stephen Walt on FP:
What really matters is how societies facing the danger of terrorism deal with it, and I worry that the reflexive responses we have seen over the past week are unintentionally aiding the terrorists’ broader purpose.

(Later) In other words, the keys to success are not bellicose speeches, mass marches, wars on terror, or continued military interventions throughout the Middle East and Central Asia. The key is calm resolution and conscious efforts to build resiliency at home. Tragedies will occur from time to time, but they cannot alter our way of life unless we allow them to do so.
Link:http://foreignpolicy.com/2015/01/16/...ist-terrorism/

He also cites a FT article (behind a registration wall) which offers a template:
What is to be done? I can’t improve on the advice of the Financial Times’ Martin Wolf, whose column this week is full of wisdom.

He offers six extremely valuable recommendations: 1) “accept that we are playing the long game of containment,” 2) recognize “that the heart of the struggle is elsewhere,” 3) “offer the lived idea of equality as citizens as an alternative to violent jihad,” 4) address the frustrations that marginalized populations feel, 5) accept the need for security measures while recognizing they never ensure completely safety, and 6) remain true to our ideals (rule of law, no torture, etc.). I would only add: Stop trying to engage in regime change and/or social engineering in the Arab and Islamic worlds, and stop using force there in an inconsistent and often indiscriminate fashion.