From Allison Stanger, "Understanding the Angry Mob at Middlebury That Gave Me a Concussion", NYT 3/13/2017 [emphasis added]:
Students are in college in part to learn how to evaluate sources and follow up on ideas with their own research. The Southern Poverty Law Center incorrectly labels Dr. Murray a “white nationalist,” but if we have learned nothing in this election, it is that such claims must be fact-checked, analyzed and assessed. Faulty information became the catalyst for shutting off the free exchange of ideas at Middlebury.
Ms. Stanger presumably meant "… if we have learned anything in this election, it is that …"
Or maybe "… if we have learned nothing else in this election, it is that …"?
Anyhow, this seems to be one for the misnegation files.
Update — in the comments, Anne Cutler suggests that the target was actually "… if we have learned one thing in this election, it is that …" This seems to me to be the most plausible hypothesis yet.
Another commenter suggests that "if we have learned nothing" has become an idiom similar to "could care less", which we've discussed extensively over the years. It's certainly true that there are plenty of other examples — in the first 30 hits for "if we have learned nothing" from the current Google News index, we find e.g.
If we have learned nothing from our nation's new secretary of education, Betsy DeVos, it's that our schoolchildren are confronting a dire threat …
If we have learned nothing from 2016 we have learned that life is messy and complicated, and things don't always go as planned.
But if we have learned nothing about mass media, it is that networks can never be content with just one success.
But the 27 other hits are all "if we can learned nothing else …"
[h/t Anne Cutler]