Not a conspiracy. A mistake. E.g. no one wanted the screwworm fly to invade NA. It was a result of factory shutdowns. That kind of ultimate cause was what I was curious about.

Your link is global not American which wouldn’t really show the effect if it was a change in US policy. But Googling you’re right, the premise is wrong.

https://www.ntsb.gov/pages/monthly.aspx