All the lead poisoning mainly.

...They say, as though we’re not currently undergoing a similar epidemic of school shootings.

I'm reading "Going Postal" by Mark Ames (1/2 of the Radio War Nerd podcast) and a bunch of the survivors of these massacres keep going "yeah I get it"

the documentary The Great Postal Heist (free link/watch) which came out this year goes into extreme detail about the political attacks against the USPS that preceded the mass postal freakouts in the 80s. frankly everyone is lucky the casualty counts were so low, because no one has been fucked with more than the post office. BOTH parties will not stop until every single mail route in the United States is privatized. people have no idea how good the mail used to be in the 20th century. this is one of the largest, immediately-consequential-to-civilians issues in modern American politics and it's almost entirely concealed/ignored.