And here I am...totally late, but here I am, flocking to this Shakespeare sonnet because...that's my shtick. ;)
That DOES fit Diplomacy well enough by itself, but...
Consider this on top of all of that:
Shakespeare's sonnets generally follow a sequence, that is, consecutive ones will often talk about the same person or topic...
The sonnet BEFORE this one, 138, is one of the most famous of Shakespeare's sonnets, and one my my favorites (and one I had drilled into my head by my Shakespeare professor in all three classes I took her for)...
"When my love swears that she is made of truth,
I do believe her though I know she lies,
That she might think me some untutored youth,
Unlearnèd in the world's false subtleties.
Thus vainly thinking that she thinks me young,
Although she knows my days are past the best,
Simply I credit her false-speaking tongue,
On both side thus is simple truth suppressed.
But wherefore says she not she is unjust?
And wherefore say not I that I am old?
O love's best habit is in seeming trust,
And age in love loves not to have years told.
Therefore I lie with her, and she with me,
And in our faults by lies we flattered be."
So, the one before this one ALSO deals with lies, damn lies and such (ie, the woman lies and says the speaker is youthful when he's old, and the speaker knows the woman's not faithful but goes along with it) but with the note that recognizing these little imperfections and having shared white lies is somewhat healthy for a relationship--
After all, "Therefore I lie with her, and she with me,"...
Lie there for, well, lying and...lying WITH... ;)
139 is also dealing with the imperfections of a relationship, but from the opposite end--138 shows how, in "Much Ado About Nothing"-style, some shared snark and white lies to one another can maybe be a good thing and lead to happiness (and bed) in a relationship, HERE...
No such taking of wrongs as being merely white lies or something to be overlooked, eh? It's a total 180:
138 shows the more fun, tongue-in-cheek, wink-friendly aspects of white lies and relationship foibles, and here it's a falling out and showing that it can bring pain...in 138, the speaker says that though his mistress claims she's made of truth he responds "I do believe her though I know she lies," and HERE...he knows she's seemingly being untrue, but no such acceptance of that there.
And on top of THAT--the subject matter...
Shakespeare's Dark Lady. Many theories who she was (it's generally accepted it wasn't his actual wife, Anne Hathaway) but if you read the sonnets as being somewhat autobiographical and "closer" to Shakespeare's life and intimate feelings than the plays...
Perhaps Shakespeare DID have a falling out with The Dark Lady in between, or perhaps they had a John Keats/Fanny Brawne situation where they loved each other but couldn't marry, and so her looks were "killing" Shakespeare as he couldn't marry her, and any explanations--that is, her "tongue"--hurt too much as well?
He DOES say "Ah, my love well knows/Her pretty looks have been mine enemies," so perhaps he's feeling spurned, or else she's caused him emotional or personal pain, or perhaps it is a feeling of longing, as 138 ends on a lighter note, the two sharing their faults and lying together literally and figuratively...here in 139, the impression is made that, instead of accepting one another, there's an imbalance, that she's too strong in some way or too alluring or too cunning or whatever else for his speaker, and so rather than shared faults making for a lighter, "Much Ado"-esque ending in 138, in 139 it's more like "Antony and Cleopatra," where the latter's persona and looks and charm all together are so overpowering that Antony is felled by it, that there is no compromise, and it brings the ruin of them both.
Cleopatra as a character WOULD fit the bill of Shakespeare's Dark Lady in some respects, though "Antony and Cleopatra" is considered to be one of his middle-to-late tragedies and his sonnets are considered to have mostly been written years before that...
Interestingly, 138, the "Much Ado"-friendly one, was disseminated to an extent in 1599, which is often roughly about the same year given for the production of "Much Ado About Nothing," so the corollary there seems all the stronger...
Following Much Ado, in 1600?
Likely candidates include "Twelfth Night" for that year (Orsino as a character at the beginning of the play DOES sound somewhat like 139's speaker if you take the speaker of 139 to be somewhat moaning and melodramatic in how he equates beautiful looks with pain and even potential attacks) and, of course...
"Hamlet" is often given between 1598-1601, with 1600-01 being the most popular years, and 1600 being the year I personally pick, just because it's a nice, round year, and it has evidence for it as well. :)
And HAMLET...well, there's some way to fit THAT saddened Dane into this if you really want to. ;)
So.
WAY more than anyone ever wanted to know or care...but yeah, it's a cool sonnet for Diplomacy. :p