Probably the most famous characteristic of chaotic dynamics is the phenomenon known formally as sensitive dependence on initial conditions, which is more popularly known as the "butterfly effect." In such dynamics a small change in a starting value or a parameter value can rapidly lead to very different outcomes from what would have happened otherwise. It was first clearly identified and labeled by the climatologist, Edward Lorenz, in 1963 in a paper in the Journal of Atmospheric Sciences.. While he showed it there, famously a matter of a sixth decimal place, it was much later that he provided the popular tale that "a butterfly flapping its wings in Brazil can cause a hurricane in Texas."
It was Deirdre McCloskey who pointed out to me a literary historical example of this from Shakespeare's Richard III. "For want of a nail, the shoe was lost; for want of a shoe the hoof was lost; for want of hoof the horse was lost; for want of a horse the knight was lost; for want of the knight the battle was lost; for want of the battle, the kingdom was lost."
So we have a version of this underlying the decision of the US Supreme Court to revoke the 1973 Roe v. Wade decision that granted the right to have an abortion, not to mention the other decisions that have just come down involving guns and Miranda rights, and so on. I think I have figured out the equivalent of that nail in the Shakespeare line that amounts to the butterfly wing flap that led to this.
It gets down to a third rate politician, the embarrassingly named Andrew Weiner, who could not restrain himself from taking photos (and videos?) of his own erections that he would send to various women. He happened to be husband of Human Abedin, who unfortunately did not dump him earlier. They stuck together, even as he continued this nonsense. Even more unfortunately she was a top aide of Hillary Clinton through all this. And even more unfortunately somehow some of these photos got onto a phone of Abedin's, a phone where there were emails from Hillary Clinton that should not have been sent.
So, 11 days before the 2016 presidential election, at a point when Hillary Clinton was leading Donald Trump in the race, FBI Director James Comey publicized a renewed investigation of how Hillary Clinton's emails had inappropriately gotton on Abedin's phone. The FBI became aware of this because they had been investigating Weiner's photographic games with his weiner and found her emails. By the time of the election it was determined that there was no there there, but the result of the publicity surrounding the renewal of this investigation set off a decline in Clinton's polls, a decline that was sufficient to lead to Donald Trump winning the election.
And the rest is history, with him appointing the justices to the court who put these rulings over the line.