The siege by Islamic State on Mount Sinjar has apparently been broken but an enduring reversal of the terrifying advances of the militants across Syria and Iraq remains highly uncertain.
Even as the US air strikes paved the way for large numbers of Yazidi to be evacuated this week, Islamic State - formerly known as ISIL or ISIS - captured eight villages in Syria and engaged the Lebanese military in the Bekaa Valley.
Meanwhile, it has consolidated in Iraq’s second city of Mosul. It has a huge arsenal of weapons seized from Iraqi troops and assets of up to $2 billion, including an estimated $3 million in daily revenue from seized oil and gas fields.
According to some estimates, Islamic State has up to 50,000 fighters, including some 10,000 to 12,000 foreigners, with the rest locals who are ideological supporters or those coerced into joining.
There is, however, something of a template for achieving success - the routing of the predecessor of Islamic State, Al Qaeda in Iraq (AQI), in 2006 and 2007.
Like Islamic State, AQI controlled swathes of northern Iraq and formed alliances with disenfranchised Sunni tribal leaders.
By turning the Sunni leaders away from AQI and deploying a surge in US troops, the US and Iraq were able to prevail.
Assisting them was widespread community revulsion at the sheer brutality of the AQI forces and its extreme brand of Islam.
As evidenced by the gory images posted on social media by Australian Islamic State fighter Khaled Sharrouf of decapitated heads being held by his children, Islamic State is similarly barbaric.
It executes opponents, crucifies religious minorities and forces entire communities from their homes.
But, says terrorism expert Greg Barton from Monash University, Islamic State has, in its own way, learned the lesson about the “hearts and minds” campaign.
It provides food, medicines and make-work programs for unemployed youth in areas it captures.
A New York Times report from the recently captured Syrian city of Raqqa detailed how local businessmen praised the rapid drop in crime and reported an orderly system of tax collection that was far more affordable than the bribes paid to the Assad regime.
According to Barton, Islamic State is “behaving a lot better in Mosul” than AQI forces.
“If that continues, they will be a much more formidable opponent,” he says.
And, unlike 2006 and 2007, the US won't be deploying large numbers of combat troops to Iraq, if any at all.
Perhaps most significant, the Sunni leaders who walked away from AQI were badly burned after the US military withdrew and Iraq’s leader until this week, Nouri al-Maliki, launched a harsh sectarian regime that punished them.
In light of this betrayal, convincing them to side with the new Iraqi government led by Haider al-Abadi - a Shiite from Maliki’s party - will be crucial and extremely difficult.