IT was always coming but the distraction of three years fighting the Islamic State meant it was set aside.
Now ISIS has all-but fallen, tensions between Middle East nations are intensifying as never before.
The fear is that proxy Sunni v Shia battles across the region will transform into major wars, with Saudi Arabia (Sunni) and Iran (Shia) the leading contenders.
Several recent events, centred in Saudi Arabia, have exposed the post-ISIS fault lines of the Middle East.
Anointed by his ailing father, King Salman, the pro-US and anti-Iranian Crown Prince Mohammed bin Salman has consolidated his power in a corruption purge that has seen 11 princes among the hundreds arrested.
Read the full article by Paul Toohey at The Advertiser (subscriber only).