Teaching, as I am this summer, a workshop on prose style that focuses on sentences, preferably long ones like this promises to be, I have been giving my students all types of sample sentences, including those with two sharply contrasting independent clauses, or what rhetoricians call antithesis, as in "Thank you for sending me a copy of your book; I'll waste no time reading it." This classic put-down by Moses Hadas, from a list of memorable insults, illustrates the main use of the semicolon.
As a life-long advocate of the semicolon in my writing, teaching, and editing, I was surprised to read not long ago of an anti-semicolon movement, hopefully small, based on the dubious premise that these valuable marks of punctuation are unmanly. (When the fork was introduced into European dining in the 15th century, it, too, was dismissed, as many things are, as unmanly.) When Michael Kinsley was editor of the New Republic, he hated semicolons so intensely that he would re-write any sentence using one, replacing it with a period; this necessitated a new sentence following the period, of course, possibly breaking the rhythm and flow of the sentence.
Kurt Vonnegut was among the semicolon haters, claiming that real men don't use them. Male writers have always been a bit sensitive about their profession, Hemingway promiment among them, fearing that a literary life is not quite the masculine thing: too much time alone reflecting, I guess, not enough time hunting or bullfighting or drinking or whatever it is "real" men do. So I suppose this insecurity, which now seems out of date, is behind whatever anti-semicolon crusade there is.
Here's an example from my textbook, co-authored with Donald Pharr, Grammar, Etc.: "What is called 'adult entertainment' is rarely adult; it is at best adolescent." (The semicolon is essential in preventing a run-on sentence, here technically called a comma splice.)
I know more about grammar and punctuation than about masculinity, even though ten years ago I created at course at the Univ. of Central Florida on the topic of masculinity and literature. Even after teaching it three or four times, I find the meaning of masculinity elusive, slightly mysterious, and overlaid with more fear than grammar and writing. And that is saying a lot.