To what extent did divisions within the Fatimid Empire weaken their claim to the caliphate?

Candidates will consider the merits or otherwise of the suggestion that divisions within the Fatimid Empire weakened their claim to the caliphate. Reasons may predate the timeframe, but they must be clearly linked to the issue raised in the question. Candidates may refer to the declining authority of the Fatimid caliphs, which weakened their claim to the caliphate; conflicts within the Fatimid Empire weakened its ability to obtain the caliphate by conquest. Fatimid religious leaders were disillusioned by the weakness of Fatimid leaders and did not provide strong support. Other relevant factors may be addressed, for example the resurgence of the Sunni orthodoxy under the Seljuks and the failure of the Ismaili Fatimids to attract support from other Shi’ites. Their defeat by the Crusaders and the emergence of powerful opponents such as Saladin ended their chances. Candidates’ opinions or conclusions will be presented clearly and supported by appropriate evidence.