When I see "pica" I think of a typeface, but from context, the author is using a different definition. Do men who want to fight find themselves craving the taste of dirt?
You cannot understand much of modern culture until you've recognized that the state's blunt suppression of the male instinct for glory has caused widespread symptoms of pica that dominate our politics, media, and online interactions.
*pica (usually uncountable, plural picas) (pathology) A disorder characterized by appetite and craving for non-edible substances, such as chalk, clay, dirt, ice, or sand. *