Nineteen-year-old Nikolas Cruz — who mowed down Parkland, Florida, high school students and teachers, killing 17 and wounding many others — had been thrown out of the same school for threatening his classmates. He had been bragging to them about having a personal armory and implying he would use it, justifiably frightening them.

Subsequently he posted a photo of that armory, including assault weaponry, on Instagram as well as a photo of a target riddled with bullet holes with the recommendation to try it as “group therapy.” He also posted photos of dead animals, well known as a hallmark of serial killers.

Where were the adults in all this? Why was the youth allowed to have or obtain weapons of any sort — assault or otherwise — after having been ejected from school for violent threats? Why were his social media postings not being tracked by the police? The kids all knew there was a problem. Again, where were the adults — not just the police, or even the politicians, but all the adults? They didn’t watch Cruz, who was clearly mental ill and clearly evil. They didn’t secure the school, although there had been so many school killings since Columbine. They abdicated.

Meanwhile, speaking of adult abdication, at hoity-toity Princeton University the following occurred:

“Anthropology 212: Cultural Freedoms: Hate Speech, Blasphemy, and Pornography,” a course on freedom of expression at Princeton University has been “reluctantly” cancelled, Professor Lawrence Rosen informed his students in an email obtained by THE WEEKLY STANDARD. Rosen’s email, sent at 2:07 p.m. on February 12, went on to say “I think it only fair that you be free, before too much of the semester has passed, to move ahead in another course of your choosing.” Last week Prof. Rosen received national attention for using the N-word in this class on freedom of expression. Some students walked out and protested the term’s use. One report, cited in Princeton’s main campus newspaper, says that Rosen asked, “What is worse, a white man punching a black man, or a white man calling a black man a n****r?” And when Rosen was met with disagreement of his use of the N-word, and on his continued use of the term in the academic setting, he said, he would use it, “if I think it’s necessary.”

Why was the course cancelled? The university claims it was Professor Rosen’s decision with “no pressure” from the administration. But the Weekly Standard continued:

One student in the class tells TWS that he believes the course’s cancelling may have had something to do with an interaction that happened “about halfway through the first seminar.” A male student of color stood up, inches from professor Rosen’s face and shouted “FUCK YOU,” this witness claimed. Just before that, a female student of color had shouted at Rosen, as the first was approaching, “do you feel safe right now.” “There was no physical contact,” this witness claims, though at the time the student feared there might be. During that class, “nobody except Rosen defended Rosen,” the student told me. Another student in the class confirmed this account to TWS.

Fear of physical contact on the part of students? Where have we heard that before? Parkland, perhaps? At least the Florida school had the gumption to throw Cruz out, even if the authorities did not follow up as they should have and averted the carnage. The student — of color or not — who stood up inches from Professor Rosen and yelled “FUCK YOU” should have been thrown out of Princeton that very day never to return.

Princeton — in the current Ivy League tradition — did a bunch of nothing. First Yale at Halloween, then Dartmouth in its library, now Princeton — our supposedly greatest universities have become our greatest centers of adult abdication, especially on the part of their administrations. Who will be surprised if violence comes next?

This abdication of adult and, quite often, parental responsibility is rampant in today’s America. This is not just due to the runaway epidemic of political correctness in our culture and its easy disparagement of traditional values. It is the Chinese Cultural Revolution-style violence that this behavior engenders. The Princeton students terrified to defend Professor Rosen in his class were not all that different from the panicked Parkland students fleeing Cruz. The Princetonians were scared for their lives to pipe up.

But what of a solution? It’s not enough to proclaim “if you see something, say something.” Unless you do something about what people say they have seen, unless they’re sure you will, you are hanging them out to dry, just as the Parkland kids were hung out. You’re not encouraging them to do it again.

It’s time to be radically proactive. At the minimum, that means protecting our schools with professionally trained armed personnel the way the Israelis do. Whether its terrorists or psychos, the threat must be stopped and it must be stopped now.

As for the Ivy League, if it cares to maintain its vaunted position in our educational system, it should quite simply wise up and grow up. The inmates are not running the asylum.

PJ Media co-founder and CEO emeritus is a graduate of Dartmouth and Yale.