David Rozado has created the website Media Analytics where you can track the frequency of various words in the New York Times from 1970-2017. This would appear to be a very useful tool for tracking the Zeitgeist. You can do something similar in Google Books, but it only runs to 2000.
Anyhow, here is his keynote graph tracking the rise of various SJWisms:
You can also track Great Power dynamics and international crises using this tool. For instance, “Russia” was getting much fewer mentions by the late 1990s than “Soviet” during the late 1980s, though it spiked upwards since 2014. But China has been growing steadily and has long overtaken Russia.