Up till the 70's it was normal for boys and girls to swim naked!
Sometimes, though not always it was required. It was pretty normal. In 1918 at the official policy at the YWCA was "bathing suits permitted". This photo was from Life Magazine in 1950. Though some pools only allowed nude swimming. Girls too. In one record we found that girls were complaining that only the boys got to swim naked and it was unfair, so they let the girls swim naked at the meets alongside the boys.
Have you ever thought it odd that our society will freak out because someone wears a sexy outfit on TV, but that same outfit may be totally fine for their daughter to wear at the beach after church?
What is modesty? Is it about an arbitrary standard created by government, a so called religious standard from your church that does not actually exist in any of our bibles? Or is it rooted in good behavior and treating your neighbor with respect and kindness?
My goal here is not to say we should all be naked or that we should all let our sexuality run free. But have we ruined sexuality, both twisting what should be pure and repressing what should be no big deal?
Can we see that modern feminism combined with the USA's state worshiping church has worked as one to erase history and create a society both perverse and prudish! That's weird, but think about it.
How? Men are emasculated and told they must not act like men while at the same time taught to have no self control. Woman are told to not act like women, their ultimate empowerment promoted in the form of the killing of their own babies. As genders are erased mental chaos ensues. Prisons are filled using misapplied charges on everything from rape that isn't, to fake pedophilia and even urinating on a tree. Everything seems arbitrary, but in the end they all serve to enrich the power people and control others through terror.
Rather than normalizing innocence, lewd behavior is encouraged even while arbitrary lines are drawn for government to punish us in witch hunts cheered by the populace as a self-righteous tool to make them feel better about their own sins and tolerance of what may be the most unjust society on earth.
Maybe history matters and we should do something about it.
-- Gavin Seim
From the 1926 American Public Health Association standards
More sources...
https://www.vocativ.com/culture/fun/fairly-recently-ymca-actually-required-swimmers-nude/index.html
http://www.frank-answers.com/frank-answers-about-swimming-naked/