https://www.techdirt.com/articles/20191120/17042843424/alexander-vindman-now-threatens-bogus-slapp-suit-against-fox-news-laura-ingraham.shtml

SLAPP suits and SLAPP threats are flying back and forth these days. The latest is that Lt. Col. Alex Vindman, who is a key player in the impeachment hearings, is threatening a highly questionable defamation lawsuit against Fox News and Laura Ingraham, because she had on a guest who suggested Vindman was guilty of espionage (he's not). The threat letter was sent by David Pressman, a lawyer who works for Boies Schiller Flexner, a law firm which has a history of sending around bogus threat letters to the media for doing reporting.

Even if you think that Fox News is terrible (it is), that Ingraham is not to be trusted (she's not), and that her guests are fools (they are), this threat is still completely bogus and silly.