ISIS and other Islamist groups have been persecuting Christians and other non-Muslims for way too long of a time to not provoke a call to arms from the Western World. On top of that is the fact that another result of the actions of these religious extremists is that Muslims are safest OUTSIDE of the Islamic world, as Muslims are now more likely to die at the hands of other fellow Muslims than at the hands of Kaffirs (non-Muslims).
Given the views of the Catholic Church and the newest Pontiff I'd say that's not going to happen. Members of Christianity might have the desire to combat threats like ISIS in the East and abroad but I don't think something like a crusade would be organized. It would undoubtedly be viewed as an imperialist move on behalf of the Church and her allies which is not the most optimal pathway right now given tensions and previous history.