Oh maybe because there was an attack on the World Trade Center in 1993. Intelligent pundits might assume the fanatics would try again... There was terrorism in the 90s, just that it was somewhere in the Middle East, on the news, so you didn't worry about it being too close to home, back then.
Ditto pandemics. There was the Spanish flu a century ago. Then I remember AIDS being all over the news, when I was a kid, then the swine flu around 2010. It wasn't as disruptive as COVID, but only loonies with crazy ideas about the Illuminati would call any of them "a weapon to devastate a targeted populace."
So thanks Solomon, there is nothing new under the sun.