From the perspective of Vision Casting, humanity can be (roughly) categorized into three cultures: The Churched Culture, the Un-Churched Culture, and the De-Churched Culture. Each culture can be further divided into sub-cultures and counter-cultures of a given category (such as race, tastes in music, and lifestyles, etc). Much of the attention, both positively and negatively speaking, has been centered on the Churched Culture; frankly, because it is the established culture of western civilization (especially in America). The Un-Churched Culture seems to always be the instigator of change. But it is the De-Churched Culture that is usually an over-looked, if not forgotten, category. Living among the un-churched the de-churched remember life as the Churched.
For better or for worse, regardless: By definition, then, the Churched are those that make up the establishment and have historically been the story tellers concerning it; the Un-Churched are those who have never been a part of the establishment and have no story to tell concerning it; and the De-Churched are those who have a memory of the establishment, but ultimately have no positive stories to tell concerning it.
Here is where most people confuse the categories.
The Churched has attempted to set the norms for society; the Un-Churched has never been a part of those norms (or that society) and, therefore, are unaffected by (and often ignorant of) such perceived norms and; the De-Churched feel victimized and alienated by these norms and, thus, the rejected (perceived or otherwise) become those who reject the norms.
As a rule (there are exceptions, which make it a rule), most of your atheists actually belong to the De-Churched Culture. Most of the Un-Churched are not a threat to the Churched Culture, except passively and by implication. It is those of the De-Churched that have abandoned “Christianity” and embraced the sciences as an alternative. They are those who target the church as enemies. The Un-Churched are oblivious to the cause and, honestly, until something changes, the De-Churched will disciple the Un-Churched, via ignorance, at an alarming rate.
All three categories do have one thing in common: All have an inert need of Jesus Christ. The Churched must remember who it is the story is concerning and make disciples of His (rather than a religion). The Un-Churched must inhale the smelling salt of the reality of Jesus Christ; not by becoming churched, but by expressing Him in and by the Un-churched Culture. And the De-Churched must realize that their memories have nothing to do with Jesus Christ, but in fact only a culture (of which they’re no longer a part), and utilize their energies and talents in telling His story. In whichever category one finds oneself – regardless of the culture – Jesus Christ is powerfully crossing cultures for the building of His Church; not a simple culture, but a composite of the three.