“What???” was my dad’s response when I texted him Friday that Neil Peart, the Rush drummer and lyricist, had died of brain cancer. I knew he’d be heartbroken, since he was a long-retired drummer who, like many, considered Peart the greatest. “Rush has to be crushed,” he texted me.

So was I. Because wherever my father and I had encountered Rush, it was a way for us to deepen a relationship that I once worried might slip away. I clung to the band as my tether to Dad, and it never let me down.

When I was a kid, I was awkward and not very athletic. I had little hand-eye coordination, despite my parents’ persistent efforts to help me improve.

That changed when I asked my parents for a guitar. I got one for my 10th birthday, and classic-rock radio became my father’s and my language. There were a bevy of bands that he and I loved. He had seen AC/DC before frontman Bon Scott died, for which I will always envy him. We both loved the Scorpions, a German group, and the Prince of Darkness Ozzy Osbourne. My second concert was when my dad took me to see the Who (whose drummer Keith Moon was one of Peart’s favorites). There was Van Halen, which split my dad and me, since I preferred David Lee Roth as a lead singer while he was on Team Sammy Hagar.

But if there was one band that truly excited my dad, it was Rush, and it was because of Peart. Whenever “Tom Sawyer” would come on the radio as we drove around, he would mime Peart’s iconic solo on the steering wheel and dashboard. Seeing him enjoy Rush that much made me want to get more into the band and learn more about this mysterious power trio that sang about Mark Twain and Shakespeare with impossibly complex guitar riffs.

My parents divorced when I was 11, intensifying my desire to find a bond with my dad, since I saw him only every other weekend. On those visits, we had Rush. We’d play a greatest hits album on the half-hour drive to his girlfriend’s house, and he’d explain Peart’s technical prowess on songs such as “Red Barchetta” or “Freewill.” He enthused over how Peart performed acts of virtuosity completely stone-faced, showing not even the slightest hint of emotion. He’d explain how difficult it was for Peart to catch the cymbals on the opening drums to “Limelight.” I occasionally sang along to Peart’s lyrics.

On Sundays, though, my sister got to pick the music. She made us listen to Top 40 radio, which deepened our bond over Rush since my dad and I agreed that pop music was so fake. We subscribed to what Peart wrote on “The Spirit of Radio”: “All this machinery making modern music can still be openhearted.” We liked to believe in the freedom of music and hoped that glittering prizes and endless compromises would not shatter the illusion of integrity.

Those moments were precious. So, when my dad remarried and moved in with his new wife, I worried most that I’d lose that half-hour where we could listen to Rush unfettered while Steph slept in the back seat. I think in my young mind, losing our Rush time somehow stood in for a fear that my dad would eventually forget about us and enjoy his new life with his new wife and stepkids.

Of course, those fears were unfounded — both in our relationship and when it came to Rush. A year after he remarried, Rush’s album “Snakes & Arrows” was released and we went to see the subsequent tour, filled with many of the geeks and nerds who listened to the band when they were kids and were now were grown up and taking their disaffected teenagers to see this same band and connect in the same way. In 2009, the movie “I Love You, Man” featured a performance by Rush, so we went to see it.

Years later, that wife is now his ex-wife, but Rush remained. When my dad drove me to the airport for a red-eye flight to my first D.C. internship, we played “Moving Pictures.” When I was in college in North Carolina and Rush won admittance to the Rock & Roll Hall of Fame, the first text I got was from my dad: “It’s about time.”

A lot has been made of the fact that Rush was a band for misfits, and, over the weekend, I thought about that even more. The Post’s Travis M. Andrews notes how it was easy to mock Rush’s “self-seriousness.” Peart’s lyrics were an easy target — Blender magazine once named Peart rock’s second-worst lyricist (it’s not a slight source of glee for me that the magazine went out of print and Peart outlived it).

But I think the reason I loved Rush is that their music was made for people who were not cool. When Ric Ocasek of the Cars, one of Dad’s other favorite bands, died last year, the Ringer said they “idled at the laser-precise intersection of nerdery and badassery.” But Peart and Rush told its fans that you didn’t need to be cool. Instead, here is a song for you about social isolation and the cruelty of suburbia. Here is a song about class conflict and trees.

My dad and I texted about listening to Rush all weekend, and he noted how since he replaced original drummer John Rutsey, Peart was not only a great musician, “but gave Rush a whole new direction.” All the while, I couldn’t help but think about “Time Stand Still,” my dad’s favorite song by Rush and the one that ended that greatest hits CD we played in the car. I just hoped for a bit we could “freeze this moment, a little bit longer/make each sensation a little bit stronger” before the experience slipped away.