And the military doesn't breed "aggressiveness" outside of specific services and roles that require it. It does demand an inordinate "attention to detail" due to the fact lives are on the line, whether that be on ships, planes or just normal activities.
This "attention to detail" is also seen among other professions, but seldom in software outside of NASA/avionics/medical/etc...
Linus has laid out guidelines and expectations which while demanding, can be followed. If you can't test your code nor follow a checklist, then maybe you shouldn't submit patches to him. It's the military equivalent of passing barracks/quarters inspections, it should be elementary for professionals.