This and its follow-up, "Enemies Domestic (2010)", are references to the oath taken by members of the military to defend the Constitution. "Enemies Foreign and Domestic (2002)" was the first of four episodes of The West Wing (1999) in which Mark Harmon appeared, and it was his commanding performance as a Secret Service agent that led to Harmon's casting on "NCIS".
Mossad Director Eli David is impressed with peanut butter-filled pretzels, saying "this is incredible,... this is American ingenuity." The peanut butter pretzel was invented by Jewish-American Max Reisman.
During Ziva's confrontation with Liat, Ziva tells her that "you have a cat named Bill." Bill the Cat was a principal character in Berke Breathed's "Bloom County" comic strip in the 1980s.
In The West Wing episode of an enemies foreign and domestic Michael O'Neill was also present along with Mark Harmon
When Liat and Ziva compare achievements, Liat claims she's not done, citing benefit of youth despite the actors being only 3 years apart.