Missouri is suing China over COVID-19, and it's just legal theater - 2020-04-22
Wait, can foreign states be sued in US courts? Usually, no, and until 1952, never.
As a matter of "grace and comity" (legalese for "do unto others…" we don't want to be sued in foreign courts, so we can't permit the same), foreign states enjoy general sovereign immunity from US lawsuits, per 28 USC §1604. Section 1605 provides a handful of exceptions to general immunity found under the Foreign Sovereign Immunities Act. None apply here.
Undaunted by reason or lack of precedent, Missouri cites two such exceptions.