The terrorism in Paris isn't about religion, nothing to do with Islam (which strictly forbids such acts) and nothing to with countries or cultures; this is about power, inciting violence against muslims (the very people they purport to represent) in an effort to increase the numbers of radicals to join their cause.
Do not play into their hands by seeking retaliation against muslims, immigrants, refugees, Syria, etc. If you do, you become as much a terrorist as these scum, as you're helping them achieve their agenda.