The Chinese Communist Party, fully aware they had an epidemic in Wuhan Provence continued to permit hundreds of thousands of passengers - many certainly carrying the virus while asymptomatic - travel yo the United States.
This was not unintentional, this was an act of Biological Warfare intended to wreak havoc in the United States.
Later same day: Seems there's already some in DC thinking along these lines (although CCPs accountability is not effectively reduced if the bug wasn't 'created' but merely leaked).
and ... catch the 6 minute mark here
4/9/20 Given any such research is, at the least, 'dual use' and monitored, if not driven by CCP's BioWar folks this story appears to identify one of the folks closely involved with the leak ...