Well you’ve intrigued me, @Coiler, into picking it up. Something about the plot sounded familiar until I got out to Amazon and saw the blurb from Rowland White. White’s non-fiction Phoenix Squadron (which I’ve not yet read) deals with a 1972 crisis between the two countries involved and the HMS Ark Royal getting involved. So the premise isn’t on quite so shaky ground, I don’t think.
And I’ve revealed the extent of my knowledge of Latin and South American politics and diplomacy! I’m vaguely surprised I didn’t come across this when I wrote my US invades Venezuela in 2003 story for another anthology.