In this case, their grievance is that we exist. ISIS wants a new caliphate to control the entire Middle East and they want to pursue holy war, you can't really negotiate around either of those even if they wanted to.
I think you misspelled "the world", basically their strategy is to generate so much resentment towards Muslims (you know, 1.6 billion people - bigger than declaring war on China) that they get two new recruits for every one that's killed. The only reason it's not working is that so far we haven't taken the bait. We grieve for the dead, increase the military effort but we don't lash out in revenge. I sorta expected some militant nutters to go postal in a mosque or to burn them to the ground but apart from a lot of very vivid commentary there's been very few actual attacks on Muslims in general. If we were as short-tempered as they are like going ballistic over drawings we'd be in WW3 by now.