I was in New York City on September 11, 2001. When the first tower was hit, I was hurrying to work. A dishevelled-looking man asked me for money, and I mumbled an apologetic ¡°no¡± as I brushed by him.?

¡°The World Trade Center¡¯s on fire,¡± he called after me.

To my enduring shame, I didn¡¯t turn around to look south towards the towers. So I didn¡¯t find out about the attack until I reached my office. Later that day, I watched both towers come down.

And over the next few weeks and months, I watched America debate the meaning and legacy of 9/11. To President George W. Bush and his Republican followers, it was a simple matter of good and evil.?. Period.

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But to liberals like me, it was more complicated than that. Of course America had to defend itself against terrorists who were bent on its destruction. But we also needed to ask why so many people around the world hated us. And that would require a??which had too often supported dictators and ignored human rights.

Nonsense, our GOP critics replied. This entire line of questioning reflected a dangerous ¡°¡±, as former US secretary of education William Bennett thundered. In a??published a year after the 9/11 tragedy, Bennett excoriated liberals who engaged in dangerous ¡°Yes, but¡± reasoning: Yes, the attacks were awful, but we also must ask how our own behaviour might have brought them on.

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That kind of discussion could only weaken America¡¯s spine and strengthen its enemies, Bennett warned, especially if it got into our classrooms. ¡°A careful, complete reading of our nation¡¯s history shows that, while we have surely had our failings, on the whole America¡¯s record is one of promoting peace and justice abroad,¡±?. ¡°Teachers must be willing to say there are moral absolutes.¡±

I¡¯ve been thinking about September 11 during the Trump administration¡¯s recent attacks on universities, which we in higher education can fairly call our own 9/11 moment. We haven¡¯t suffered direct physical assaults, but we are surely under threat from forces that wish to destroy us. When Christopher Rufo, the leading intellectual advocate for the attacks, says he wants universities to suffer ¡°¡±, it¡¯s reasonable to say we¡¯re facing existential terrorism.

Millions of dollars in federal funds have been cancelled, including money for life-saving medical research. Scholars are scrubbing their grants of words like ¡°diversity¡± and ¡°women¡±. And international students are cowering in fear, worrying that their visas might be revoked for something they said or wrote.

Of course universities must protect themselves, just as America did after 2001. Since that time, there hasn¡¯t been a single large-scale foreign terrorist attack on American soil. We should all be thankful for that.

Likewise, I¡¯m grateful that our universities ¨C after keeping quiet for months ¨C are finally standing up to the assaults. Last week,??with a White House letter demanding that it submit to government direction over hiring, governance and admissions. And it turned up the heat this week by??for allegedly violating the First Amendment of the Constitution and a spate of federal laws.

Again, good on Harvard ¨C and on the? ¨C for fighting back. But that shouldn¡¯t prevent us from asking why so many Americans dislike universities in the first place. In 2015,??57 per cent of adults expressed strong confidence in higher education. By 2024, that number was down to 36 per cent.

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Of the people who weren¡¯t confident in us, 41 per cent cited our political agendas: we were too liberal, or we were trying to indoctrinate students to share our biases. About a third said we weren¡¯t teaching useful skills, and a quarter said we were too expensive.

We can¡¯t blame all of that on President Trump. Instead, we should be wondering what we did ¨C or didn¡¯t do ¨C to create such fertile ground for his attacks. How did many schools become?? Why does?? And why does??

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But when I raise those issues with colleagues, they take the William Bennett position: we¡¯re good, and our opponents are evil. Suggesting otherwise just gives ammunition to the enemy. Bennett called that moral equivalence; we call it?.

Look at all we do for America! We fight disease, we invent new technologies, we prepare democratic citizens. Any careful, complete reading of our history will demonstrate that. But some Americans are so blind that they can¡¯t see this. They¡¯re racist. They¡¯re anti-intellectual. Or they¡¯re simply in the death cult of Donald Trump, who has pulled the wool over their eyes. The problem is with them, not with us.

But academics are just as wrong about that as Bennett was about the liberal reaction to 9/11. Like the hijackers, some of our enemies in 2001 were indeed hateful zealots who simply wanted to kill and maim. But many decent people around the world doubted our goodwill and behaviour, and we couldn¡¯t understand the moment unless we listened to them.

Likewise, we can¡¯t comprehend the threats to universities if we dismiss every critique of them as ignorant or misguided. And asking how we might have erred doesn¡¯t empower Trump, any more than examining American foreign policy in 2001 played into the hands of al-Qaeda.

We must fight threats from the outside, but also look inside to see how we can get better. This really is our own 9/11 moment. The question is whether we can learn the hard lessons of the last one.

is professor of the history of education at the University of Pennsylvania and serves on the advisory board of the??He taught at New York University from 1996 to 2016.

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