Qs on crusading for this day and age

Under what conditions may the Catholic Church declare a crusade? Who may declare a crusade? What are the chances of a crusade being declared in this day and age? Against whom/what would it be declared?

What about the above questions for any other Christian denominations?


The Church does not weild any significant political power in this day an age. I suppose that in theory the Pope could declare a Crusade, but who would be around to follow it. The original Crusades were driven by a belief that the Crusaders would have all their past sins forgiven if they joined, but since the Church’s stance on the afterlife has changed a bit in the intervening nine-hundred years, it’s difficult to say what motivation could be offered now.