Well, I know the answer because is familiar for me and in my perspective the anti-imperialists thought that the united States colonizing of some countries wa fueled by greed. I hope this help you.
Answer:
The revival of Romantic spirit,
Explanation:
The age of Johnson refers to a period of time when all major/famous poetry publication was dominated by a poem named Dr. Samuel Johnson.
Before the age of Johnson , the theme of popular Poetry was mostly classical (which revolves around honoring tradition / culture in a certain society). Samuel Johnson was an important figure who introduced Romantic Themes in poetry (which revolves around humans and their emotion) . As a result, other poetry with this theme started to emerge and became popular between 1744-1784.
I answered this on your latest post. No plagiarism either.