Western foreign policy is a pathetic excuse for all these Islamist terrorist attacks. If anything western foreign policy has been assisting ISIS and other Islamist terrorists (certainly that has been the case in Syria and Libya). Anyway, ISIS have killed more Muslims than anyone else. They have killed, tortured and brutalized religious and ethnic minorities who have got nothing to do with western foreign policy (Coptic Christians, for example). Their supporters (such as the Manchester suicide bomber and the three Islamist terrorists in London) don't care about foreign policy. They are just angry and frustrated because Islam can't be imposed on western society. That's why they targeted pubs and a pop-concert for young girls.

If we have a failed policy it is a failure of integration or domestic assimilation not our foreign policy.