 Historically, the inner rifts within Islamic ideology were to be hidden from the public sphere, while the new violent outbreaks highlight said rift in an obvious manner and is nourished by the two extremes of their mutual rivalry which will strongly affect both globally and regionally.At least one scholar sees the period from the collapse of the Ottoman Empire through the decline of Arab nationalism as a time of relative unity and harmony between traditionalist Sunni and Shia Muslims—unity brought on by a feeling of being under siege from a common threat, secularism, first of the European colonial variety and then Arab nationalist.An example of Sunni–Shia cooperation was the Khilafat Movement which swept South Asia following the defeat of the Ottoman Empire, the seat of the Caliphate, in World War I. Shia scholars "came to the caliphate's defence" by attending the 1931 Caliphate Conference in Jerusalem, although they were theologically opposed to the idea that non-imams could be caliphs or successors to Muhammad, and that the caliphate was "the flagship institution" of Sunni, not Shia, authority.