Why weren't nuclear bombs used in e.g Vietnam and Korea? Was it ever on the table, and if so, what held the US back?

I've always been curious, especially of the latter - was sending a message to those oppressed by Jim Crow a primary purpose of erecting monuments of these Confederate persons? Why were they built in the 19th century, the early 20th or the mid-20th century?

I've tried to Google the connection between the black stone of the Kaaba and its link to pre-Islamic religions but did not find much and found a lot of people writing to try to spook readers from Islam.

Anyway, trying to find out more about worshiping unusual stones such as the black stone of the Kaaba.

My guess is that it was probably something like census books, but it seems like the first time someone went "Hey, I'm Bob, the son of Fredrick. I'm Bob Fredrickson! ." would be a weird transition once their kid was also named Fredrickson, when traditionally they would have been Bobson. Was it an immediate thing that can be pinpointed in history?

Not simply describing the concept of gravity, but when was the first time a word was used to call the force gravity or it's equivalent in whichever language it happened to be in?

Women in renaissance paintings often look quite ugly with a male-like waist figure, why is this?

Thinking specifically of mercenary involvement in places like Rhodesia and the DRC, but anywhere will do

In A Knight's Tale, which takes place in 14th Century Europe, Count Adhemar mentions that William is "jousting in an antique," joking that his grandfather can wear his in public again, pointing out that William's armor has a shield over his arm as part of the armor, whereas most other nights simply have a large pauldron on the left side.

This made me wonder, would fashions change so quickly among knights and nobility? Would a separation of one or two generations bring about such drastic shifts in what was in style? Armor seems like too expensive and precious of a thing for them to worry about fashion, though this movie takes place in the landscape of tournaments and leisure, so the nobles participating had more resources to consistently change fashions, so I could see it going either way.

I assume style of clothing changed quite a lot faster than trends in armor, especially those mediated by fashion and not function.

I'm specifically interested in France and medicine, but really curious in general if the concept of "studying abroad" was taken the same way that it is today.

Was it common or expected for certain fields? How did universities and education at that level compare to that of America?

Like why did people settle in places like Oymyakon? Where the temperature is routinely below fifty degrees centigrade, did they reach this frozen patch of Earth and think 'Right, this place looks good to live.'

It seems like something that would be an easy answer to find but I can't seem to find anything that is credible, or has reliable sources. Which came first in mathematical history, the use of fractions or decimals? We are taught fractions in grade school first, then later decimals curious is that is related to the history behind them.

I watched Bob Hoskins play him in the film enemy at the gates, I'm not sure how accurate a portrayal it was, but I'm still curious as to how he managed to keep his head down at a time when Stalin was executing so many senior officials

There was no internet back in those days. Was there alot of money put into marketing? George Lucas was not a very well known actor.

With the decline of armor in European warfare starting in the 16th and picking up in the 17th Century (so that by the mid-18th Century hardly anyone wore it on the battlefield besides some cavalry units) was there a corresponding increase in average battle casualties (as a percentage of army size)? Or did some other change in technology or tactical and operational procedure compensate for the decline of armor?

If proportional casualties didn't increase, was early modern ranged gunpowder combat inherently less deadly than a late medieval melee? Or to put it another way, did battles in the mid-18th Century have higher average casualty percentages than mid 15th Century battles, and if not, why?

Searched high and low and read a lot of documents/looked over some maps, but I can't seem to find anything about the history/layout of Mt. Vernon Square.

With as meticulously as Washington DC was planned out, it would seem that Washington Circle & Mt. Vernon Square should mirror each other (both circles or both squares). I would have thought it would be a circle, given the close proximity to the others in the area, but perhaps I'm missing something that prevented this from happening, i.e. existing structures.

Was this originally a circle (or supposed to be)? Is there any documented evidence as to why, during the planning, this area ended up being a "square?"

So I just learned about how after the defeat at Carrhae Crassus was humiliated in a brutal way together with multiple Roman captives, by parading the mutelated head of his son and Roman soldiers around Mesopotamia, and the act of killing the man in and of itself. I also recall Valerian, after his capture, being used as a footstool for the Sassanid Emperor for the rest of his life. Were Persians/Parthians/Sassanids keen on humiliating their enemies in such an extreme manner? Was it considered to be particularly insulting or horrific at the time and was it any different from what rival states did?

I know this may be a dumb question, but I was wondering what unit of measurement they used to tell the year before the AD/CE system was implemented. Also, wasn't it based off of the seasons, and not the actual months, or am I thinking of another calendar system?