Islamic State (ISIS) has expanded its audience, footage posted last week reveals - this time, targeting older men. 

A new video posted by ISIS terrorists to social media shows two speakers, both in their fifties or sixties. The men clutch Kalashnikov assault rifles in their hands and sit in controlled, military guard stances. Captions say the two are specifically assigned to patrol units. 

One explains to the camera that the "only reason" he joined ISIS is the "desire to defend Islam." 

To the West he sends a message: "We love death as you love life." 

They conclude by boasting to the camera that ISIS will overcome Western coalition forces, as well as Shi'ite groups on the ground. They pledge allegiance to Caliph Abu Bakr al-Baghdadi before calling on more Muslims to help ISIS in the Islamic holy war. 

ISIS's social media campaign has reached out to a number of demographics, most notably teenagers and young adults from the West. 

However, the new footage deepens the sense that ISIS is building a Caliphate by purposefully assigning each recruit to a different role, based on background, age, and gender. 

Thousands of women - from the West and from the Middle East - have also flocked to ISIS.

But more than just vehicles by which to create a population boom in the Islamic State, ISIS propaganda videos have specifically aimed to recruit baby-sitters and housekeepers as much as they have wives. 

Ethnicity plays a role in ISIS recruitment as well.

Western recruits, for example, have been tasked - whether by volunteering themselves or by others is unclear - to publish social media posts lauding the group in their mother tongues, expanding the recruitment field abroad. 

And according to "War Nerd" Gary Brecher from Pando Daily, a disproportionate number of suicide bombers from ISIS are Saudi - nearly half - not because of religious differences between ISIS and Saudi nationals, but because, according to Brecher, they are the "least useful" to them. 

Child soldiers, in general, appear to be recruited to do much of ISIS's dirtiest work: going into the most dangerous areas to fight on the group's behalf. 

According to the UK's Independent, the group has established “training camps to recruit children into armed roles under the guise of education."

Child soldiers are trained in Islam and military tactics from ages 8 to 15. According to a UN report, “the existence of such camps seems to indicate that ISIS systematically provides weapons training for children. Subsequently, they were deployed in active combat during military operations, including suicide-bombing missions.”

The UN also found that young children are frequently used by various committees in Syria as "messengers, spies and guards," as well as informants, "which exposes them to retaliation and punishment."