The gradual decline of a society is often a self-induced process of trying to meet ever-expanding appetites, rather than a physical inability to produce past levels of food and fuel, or to maintain adequate defense.
A guy is a lump like a doughnut. So, first you gotta get rid of all the stuff his mom did to him. And then you gotta get rid of all that macho crap that they pick up from beer commercials. And then there's my personal favorite, the male ego.