You're probably reading a lot of articles first about the demise of the Islamic State and then about a possible comeback of Islamic State and yet you cannot imagine it from a practical point of view. Actually we've been already there, couple of times at least. This time is bigger
Just imagine a thin structure formed by one thousand men or more scattered in the Levant, Turkey, Maghreb, the Gulf, Europe, AfPak and Southeast Asia. They are well shaven, run normal activities, have legit passports, bank accounts, clean criminal records
They don't have special qualities or resources, except for their clandestine zeal and their readiness to do whatever is necessary to bring back the Islamic State. On the long term they could either die or bring unspeakable violence on civilians, it doesn't bother them
To be clear, I'm not talking about the marauders of Islamic State in Iraq running a replay of year 2012 these days. The men I'm talking about didn't expose themselves publicly during "the Caliphate years", they are the human equivalent of caches of weapons buried in the desert
This case for instance (he used al Furqan videos as educational material during the lessons he gave to children between 4 and 10 years of age – one is the quite gory "Until There Came to Them Clear Evidence" April 2015 judging by description)
This could be another one, a leader living undercover in Turkey in an area for tourists much far from the border with Syria
While Islamic State fighters trapped inside the vanishing strip still under their control are focused on the next ten weeks, the men in the external ring have a vision and think about the next 10 years. Pics: old leaders quietly at business 
Abu Hamza al Muhajir, who will become the most wanted leader in Iraq, run a Pepsi kiosk in Baghdad in 2002-2003 while laying the groundwork for Zarqawi's group. Until recently, the Islamic State operated a legit front-company in Turkey which bought drones worth $500,000
At the top of their list of priorities is: getting money. They don't have special skills to offer on the market except they are ruthless and dedicated, so they are going to act like a local mafia: embezzlement, extortion, smuggling, real companies
2nd thing: keeping a connection with their people in jail. Iraq alone holds 20,000 people on terrorism links. One fourth could be sentenced to death. The rest is like the Jurassic Park's mosquito preserved in amber, you can create a new class of monsters from it
3rd thing has already started: create a long list of the enemies of Islamic State and kill them one by one. These murders are below the threshold of visibility, while international media is inevitably consumed by stories about pornstars and presidents. They matter though
I think they are not rushing toward the Caliphate again, toward that territorial control which proved so costly and short-lived. The game will be for a long time a sort of narco war like in Mexico: killing the opponents, doing business, reducing the local authorities to impotence
