Oh ok..your emphasis is on isis vs ummah..While I went a step ahead (if you don't mind)..general tendency of Muslims is to blame their failures and shortcomings on external forces...
For E. G. Taliban, AQ, ISIS etc etc is being credited to Israel, US, UK...While the pakistanis credit isis, ttp to India and taliban to the americans..they also tend to blame every other non muslim country including russia..China for their miseries.
Also general tendency to justify wahaabism and extremism on external factors...they blame every known intel agency and non muslim nation for "funding" their own terrorists.
For E. G. If you ask the turks..they might blame Iran russia Syria for Isis. .Pakistanis will blame RAW for Isis, the Iranian will blame the Israelis for Isis. ..the Saudi will blame the Syrian, the shia, the Iranian for Isis...the rest will blame the Russian the burmese the Chinese for the alleged atrocities on their muslims which fuelled recruitment from their countries into isis...same goes for the west..For not providing Shariah zones in Britain and France. .isis ranks are swelling with "British and french" recruits.
Assuming they bring all these countries together and each having its own enemies and it's own agendas..which essentially means the ummah is up against most of the world and it's agencies before they set out to war with the isis.