Twenty years ago today, I was sitting at my cramped little desk in the Capitol complex, wedged in a hallway between a printer and a coffee machine. The live TV feed in the corner of my computer window showed one of the World Trade Center towers with a hole and plume of smoke billowing out of it. I instant messaged a friend through my AOL chat window, asking what was going on.

Before he could respond, the second plane hit the other tower — and then the police came in shouting for us to get out of the building as quickly as possible.

I ran out of the Longworth House Office Building onto the street, and in the throng of terrified faces, I managed to find my old boss Bernie Sanders by searching for the disheveled shock of white hair (a trick I had learned during years of being his press secretary). Bernie had been mad at me for recently leaving his office for another gig, but that all went away in the trauma of that day.

We spent the day watching TV at a Greek restaurant, my parents back in Philly worried sick because the cell service was out on my BlackBerry and I couldn’t let them know I was OK. Later that night, I was there when every member of Congress gathered on the Capitol steps to sing “God Bless America.”

The next few months were a blur of fear and loathing. Like many others, I had to take Cipro during the anthrax attacks, I had to duck at the gas station for fear of being gunned down by the mysterious DC sniper, and I had to flee the Capitol more than a few times during repeated bomb scares.

As the spokesman for Democrats on the House Appropriations Committee, I visited Ground Zero during the cleanup with my boss, Rep. David Obey (you can click here to see some of the photos I snapped). I worked every day with him to try to stop the Bush administration’s “war on terror” power grab and its callous disregard for basic humanity.

Immersed in endless images of death and destruction and trying to wage a politically impossible fight against neoconservatives in the White House, I started having an uncontrolled tremor in my left hand and was convinced I had a horrible disease — only to find out that I instead had developed an anxiety disorder that I still periodically struggle with today.

I don’t talk much about my own experience on 9/11, because it’s not that interesting and the trauma I experienced was tiny compared to not just the death and destruction on that day but the suffering that grew out of the catastrophe. The attack itself was a grotesque act of mass violence perpetrated by monsters — and then another set of monsters cynically weaponized the event as a justification for everything from an assault on civil liberties, to a surge of bigoted Islamophobia, to drone murder, to an entire war based on lies.

“The events of twenty years ago could have been a chance for Americans to realize what kind of impact the foreign policies pursued in their name have had on millions of ordinary people around the world, and to change course before more blood was spilled,” wrote Jacobin’s Branko Marcetic. “Of course, that’s not quite how it went.”

The whole thing is so painful to ponder that I want to forget it — and sometimes I think that is why many have allowed their rightful revulsion of Donald Trump to convince themselves that the Bush administration and its cheerleaders actually weren’t so bad.

As the years go by, it’s easier and easier for many to embrace that falsehood — the distance of time can dull horrible memories, especially memories of the unfathomable crimes and pain of the 9/11 era. It’s apparently so easy to revise history that a majority of Democrats now have a favorable view of George W. Bush, and his accomplices continue to be rewarded with lucrative media platforms, even at putatively liberal outlets.

But we shouldn’t memory-hole what happened. We should learn from it — and the optimistic part of my brain wants to believe that perhaps that’s finally happening.

One obvious lesson is that the policy of endless war is a disaster. The long-overdue withdrawal from Afghanistan suggests that maybe that lesson is finally being absorbed even by the unlikeliest of people — President Joe Biden, one of the most influential Democrats who helped lead America into the Iraq War.

Another lesson is that we can always afford to do big things; it’s just a question of whether we choose to do big bad things or big good things.

Since 9/11, we have spent $21 trillion on militarism, which translates to more than $2 billion every single day for twenty years — all rationalized as an appropriate response to a terrorist attack. That money could have been spent to provide adequate medical care, world-class education, decent housing, and a clean environment to everyone in the country. Perhaps a new $3.5 trillion reconciliation bill could be the start of a long-overdue shift in budget priorities — and the beginning of real investments in something other than nihilistic violence.

But maybe the most important lesson is about resisting the demagoguery of political opportunists.

Three years after 9/11, Bush based his run for reelection on attacking Democratic nominee John Kerry for the allegedly unforgivable crime of suggesting that we should not let terrorism define our identity as a nation.

“We have to get back to the place we were, where terrorists are not the focus of our lives, but they’re a nuisance,” Kerry said, arguing that stopping terrorism should be seen as a law enforcement matter, not a rationale to transform the country into a martial state.

Bush and his cronies scandalized the sentiment, and — with the help of an obsequious corporate press — a saber-rattling country in the throes of bloodlust cheered it all on, creating disastrous consequences for an entire generation.

You can blame Kerry for uttering a taboo truism in the heat of a campaign, but that misses the deeper problem: our politics, media, and national discourse so often reject even the most rational ideas when those ideas can be dishonestly demonized by bad-faith villains.

If we’re going to solve the huge problems in front of us, that has to change. We have to be able to accept facts and listen to each other, even when those facts might make us uncomfortable and even when we may disagree. That is the spirit of our work — and it must become the ethos of our whole society.

We must understand that the 9/11 era helped create a modern version of the Dark Ages. And we must also understand that the future of our country and our planet relies on us all doing the opposite as we turn the page and finally begin a new era.