I’m not sure that positivity died with 9/11, but I can look back and recall a large number of people struggling after the 2008 crisis, and whole economies never entirely recovering, and so optimism had taken some hard knocks well before 2015/2016.
Remember how one of the early episodes of Portlandia around 2012 waxed nostalgic about the 1990s as a sunnier time?
Remember how one of the early episodes of Portlandia around 2012 waxed nostalgic about the 1990s as a sunnier time?