Porter's "Pale Horse, Pale Rider" details a story from her life during World War I, where she was faced with mortality, both hers and that of the people she loves.
The events and fears detailed in the story nicely compare to the Vietnam War era. From the mid-50s to the mid-70s, the United States carted off millions of its young men to fight in the jungles of Vietnam. More than 50,000 US citizens died in those jungles. Of them, 61% were 21 or younger.
It makes sense that the protests in the United States were largely run by college students and young adults. These young people saw their friends and loved ones, like Miranda saw Adam, sent off to war and killed.
There are countless memoirs, documentaries, movies, novels, and plays about the Vietnam War. One of the reasons for this is that it was a period in American history that drastically changed the way we looked at war and death. It was the end, perhaps, of the era where America was a global policeman. "Pale Horse, Pale Rider" details a similar shift in thinking on death, war, and disease.