Above all is why France or rather Paris, specifically, was chosen.ISIS, an extremists and terrorists organization is making attacks worldwide to imply their threat in common man, besides , in recent past , multiple such attacks were made, in Libya , turkey and many other countries but those were on single target, has claimed the responsibility of attacks on Paris.
France, major coalition partner of US in war against terrorism, had participated actively in Afghanistan & in Iraq, between , supporting financially & morally, France also sent forces to help US in both Afghanistan & Iraq.
ISIS , since it arose as a threat to world peace, was trying to make impact in an organized way , and since many people in France didn’t want , to get involved with others or coalition wars rather, people went to join ISIS, and obviously wherever the place is attacked, local people are involved.
To review the policies was needed in France but the Europeans neglected the emergence of ISIS with this much terror, they rather focused on bombing Syria, they didn’t think that this will come with a revenge, as Al-Qaeda use to do, they supported the attacks on different countries & now they are facing their outburst.
After initial investigations, all the attackers were found to be of European origin.
Third world countries like Pakistan must make definite efforts but recent attacks have made it crystal clear that work has to be done thoroughly & indiscriminately.