Just a little history of the term FYI because it seems to be thrown around a lot here without knowing the background.
"Know-nothingism" derives from the Know Nothing party of the late 19th century that was known for its anti-immigration views. The Know Nothings originally held secret meetings and would tell people "I know nothing" when asked about it. So it was not originally a derisive term.
Then starting in the 20th century, nativist political sentiments (and this includes the "America First" mentality espoused by our current president) was called "know-nothingism" by liberal commentators.
So now it has morphed into a term of derision, however it still maintains its attachment to nativism, although anti-intellectualism is obviously a big part of the stereotype.
This is all to say that yes, know-nothingism is sort of a shorthand for Trumpism as far as I can see it, so it's kind of a truism to say that know-nothingism is prevalent on the right. As far as whether it's poisonous, or equally as poisonous as the cultural relativism of the left, I will demur.
"Know-nothingism" derives from the Know Nothing party of the late 19th century that was known for its anti-immigration views. The Know Nothings originally held secret meetings and would tell people "I know nothing" when asked about it. So it was not originally a derisive term.
Then starting in the 20th century, nativist political sentiments (and this includes the "America First" mentality espoused by our current president) was called "know-nothingism" by liberal commentators.
So now it has morphed into a term of derision, however it still maintains its attachment to nativism, although anti-intellectualism is obviously a big part of the stereotype.
This is all to say that yes, know-nothingism is sort of a shorthand for Trumpism as far as I can see it, so it's kind of a truism to say that know-nothingism is prevalent on the right. As far as whether it's poisonous, or equally as poisonous as the cultural relativism of the left, I will demur.