Question: Is there a qualitative difference, or in the sense of finality, or irreversibility or changeability, some negative connotation, e.g. fate may be affected by future actions, but fait accompli is not?

Since there can be many shades or a broad spectrum of meanings of a word, I am trying to understand what is the intersection of the two spectra. The reason I ask this question is that I wrote a few lines of poetry which allude to many things and can have multiple interpretations. I'm trying to understand how much of a poetic liberty I have taken, and how much of it will be understood by the reader. I could just mention the lines, but it is unpublished and therefore, did not want to post it yet. I kept the question broad very intentionally so that I could see what comes to the mind of the people as the first sense of these words, but did not expect negative comments without an attempt of an answer, especially when I cannot respond to the "user" directly.

**Details:**

Definition of fate
1 : the will or principle or determining cause by which things in general are believed to come to be as they are or events to happen as they do : destiny
… fate sometimes deals a straight flush … he had no idea that he would become the right man in the right place at the right time … —June Goodfield
2 a : an inevitable and often adverse outcome, condition, or end Her fate was to remain in exile.
b : disaster; especially : death The villain met his fate at the hands of the hero.

-- <https://www.merriam-webster.com/dictionary/fate>

plural faits accomplis \ˈfā-tə-ˌkäm-ˈplē(z), ˈfe-, ˈfe-ˌta-, -ˌkōⁿ(m)-, British usually -ˈkäm-(ˌ)plē(z)\
: a thing accomplished and presumably irreversible
he charged that the members were presented with a fait accompli instead of being called to a meeting to discuss the policy change —Daniel Thomases

-- <https://www.merriam-webster.com/dictionary/fait%20accompli>

Answer: 
Apart from the fact that 'fate' and 'fait' sound similar, 'fate' and 'fait accompli' have nothing in common. They mean different things. 

> 
> fate noun UK ​ /feɪt/ US ​ /feɪt/ ​ B2 [ C usually singular ] what
>  happens to a particular person or thing, especially something final or
>  negative, such as death or defeat:
> 
> 
> We want to decide our own fate. His fate is now in the hands of the
>  jury. The disciples were terrified that they would suffer/meet the
>  same fate as Jesus. ​ B2 [ U ] a power that some people believe causes
>  and controls all events, so that you cannot change or control the way
>  things will happen:
> 
> 
> When we met again by chance in Cairo, I felt it must be fate. Fate has
>  brought us together.
> 
> 
> 

[Cambridge Dictionary](https://dictionary.cambridge.org/dictionary/english/fate)

'Fait accompli' is a French phrase meaning an 'accomplished fact', one which leaves no room for argument. If my wife and I decide to buy a car, and I want a Honda, but she wants a Toyota, I might seek to win the argument by buying the Honda and presenting that fact to her as a *fait accompli*.

> 
> fait accompli noun [ C ] UK ​ /ˌfet ə.kɒmˈpliː/ US ​ /ˌfeɪt
>  ə.kɑːmˈpliː/ plural faits accomplis ​ something that has already
>  happened or been done and cannot be changed:
> 
> 
> The policy change was presented to us as a fait accompli, without
>  consultation or discussion.
> 
> 
> 

[Cambridge Dictionary](https://dictionary.cambridge.org/dictionary/english/fait-accompli)
The difference between *fate* and *fait accompli* is the same as the difference between [chalk and cheese](https://www.phrases.org.uk/meanings/chalk-and-cheese.html).

*Fait* means exactly the same in French as does *fact* in English. Aside from its pronunciation (in the US), it has nothing to do with the English word *fate*.