I was looking up the rule about italicizing foreign phrases and found an apparent consensus that the criterion is if the phrase is familiar. Well, who gets to decide that? I know perfectly well what "fait accompli" means, and I don't know French. So I recently chose to not italicize it, but someone had a different opinion.
Here is a summary of my findings.
Loanwords or phrases that have common use in English, however—praetor, Gestapo, samurai, esprit de corps, e.g., i.e.—do not require italicization. If looking for a good rule of thumb, do not italicize words that appear in Merriam-Webster Online.
The University of Minnesota recommends:
Italicize isolated words and phrases in a foreign language if they are likely to be unfamiliar to the reader.
Capital Community College Foundation Guide to Grammar & Writing says:
If a word or phrase has become so widely used and understood that it has become part of the English language — such as the French "bon voyage" or the abbreviation for the latin et cetera, "etc." — we would not italicize it. Often this becomes a matter of private judgment and context. For instance, whether you italicize the Italian sotto voce depends largely on your audience and your subject matter.
University of Sussex Guide to Punctuation notes:
If you are not sure which foreign words and phrases are usually written in italics, consult a good dictionary.
"Fait accompli" appears unitalicized in Merriam-Webster Online. I was not able to find an online English dictionary that was different. I don't have access to the OED.
Is "fait accompli" likely to be familiar to readers here? Is this a good guideline to use for choosing whether to italicize it? Or is the fact that it is in English dictionaries unitalicized enough? Or is the fact that it is in English dictionaries—at all—enough?
Note: I recognize that italics are appropriate when referring to a phrase rather than instantiating it—in any language. I've instead chosen in this question to use quotes to clearly separate the issues.
Edits to correct grammar welcome. No comments necessary.