1733443200 is even more unambigous. Or is it? The date format measures how many sun-ups so it is more accurate even if time-dilation. So date format is actually just a sun position measure? Maybe we could just have a sun-ups since 1970 ticker.

Edit: and i guess why have leap seconds and stuff is because we are rrying to combine both sun position and elapsed seconds idk

OP’s backup choice is December 7, 1941.

It's the most appropriate possible example here because for many non-American readers it will be the one date that they have heard spoken in American English enough times to recall how Americans say it. For people who don't have much connection to American culture, it may well be the ONLY date they have ever heard spoken the American way in their lives.

(Indeed, this one specific date gets said the American way even in British English. We Brits don't do that for any other dates - we say "fourth of July" instead of "July fourth", for instance - but "September 11th" aka "9/11", uniquely among all dates, is written and said the American way in all dialects of English on the planet due to its significance to American culture.)

They were in a transitional phase of independence.