[reconeil]

Believe you're partially right for such being about a lost or unaccounted for nuclear device. Remember same expression used in a John Travolta movie,...where Old John played the thief of such and/or one of The Bad Guys.

Regardless, SuperScout is also right, since my understanding is that in Vietnam if a Unit Commander thought it inevitable being overrun by an exceptionally overwhelming in numbers force,..."Broken Arrow" was used as a plea for every possible bit of Air & Artillery Support that The U.S. & Allied Forces could muster.

Fortunately, at LZ-Xray things worked out well for my alma mater or "The A-Troop" of then called: "First of The Seventh" or HHT 1/7 CAV SQDN (basically a 395 man recon. battalion), nicknamed; "DESPARADOS" (Great Warriors & bad spellers).
Well,...at least the survivors of LZ-Xray were fortunate, anyway.

The: "Second of The Seventh" Squadron wasn't as lucky, due Big Brass SNAFU which damn-near got them all wiped-out afterwards. Guess "Brass" figured "Charlie" wouldn't hold a grudge about previously suffering over 1,800 deaths (plus no doubt Twice as many wounded), at same LZ-Xray?
Well,..."They" were dead wrong.

Neil