Melting Pot: Spiritual Warfare

What a facinating topic--spiritual warfare. I knew on some levels that it existed--I believe the Bible, thus I believe that the devil exists; however, I am very naive to the impact he can have on our lives. I just returned from week 2 of the class I'm in, and one of the things that I was most intrigued by was that spiritual warfare isn't just about the devil. In many ways it is, but it encompasses much more. I've heard our pastor speak about "shoot in all directions" in regards to evil or the possibility of evil, but didn't really get why. I am now understanding that quote.
From Eph 2:1-3, spiritual warfare equates to the devil and/or world and/or flesh. I generally thought that all that was bad was of the devil--and I suppose can be if boiled down far enough; but one thing I didn't fully understand is the other two aspects. I could go on and on about them, but I want to point out an interesting fact that I've learned tonight.
As we grow up, we experience "life"--sometimes through the viewpoint of others, sometimes by the viewpoints of others. As we are told not to, we tend to conform to others because we want to be "good" in their eyes, or follow what they say. I'm not attempting to pass blame, but this is one avenue where the devil uses to establish some potential life-long footholds that we will inevitably stuggle against. At some point in our past, a belief system had been established (i.e. self-beauty, self-image, habits, etc), and while not necessarily bad--they typically turn that way due to the fallen world (just look at the education system, health system: both great systems in concept, but have fallen as well). This belief system instills a program in our being (often influenced early on by the devil), but being a program in our being--continually runs w/o evil input. See Romans 7:18-25. The part where a novice like myself is that I will rebuke the devil in a particular area, but if I'm not addressing the root cause, or program--the devil just blinks an eye because I'm not doing anything to prevent the program from already running. The tough part to the solution is to identify the root program, ignore the outputs of that program, i.e. thoughts, and follow the light and utilize the sword of truth to cut up that program; now the devil will attack further because I'm hitting the nerve of the problem, and that's where I can rebuke him and lean on the Holy Spirit.
Another facet is the discernment of what is a "bad" program/thought. I've run into this much--which thoughts are "bad"/"good"--pretty much a lack of discernment. Which in some ways is good and bad. Individual discernment is tragically fallen as it leaves no accountability and straying from the flock is easy. Discernment needs to happen in community where the thing needing discerning is tested by others in that community to validate the truth or lack there of.
It's all quite interesting. Quite exciting as well. Lastly, an interesting concept of the devil: equate the devil to CO (carbon monoxide)--a silent, untastable, unsmellable, invisible force that will kill you in the right quantity.