Saw an article once about how real meditation isn't about perfect silence but handling distractions. Your comment about survival training nails it. The moment you try to clear your mind is when every random thought, or juice box crisis, attacks. Sounds like you've got some firsthand experience with the chaos.
Maybe the real trick is making the chaos your focus instead of fighting it. You stop trying to empty your mind and just watch the wild show happening right in front of you. That messy awareness might be the purest form of zen you can get.