She was maybe 4-10, when she stood on the curb in her tippy toes, this wispy 19-year-old West Chester University sophomore named Caitlin Renner - a couple of nose rings, clear-framed glasses, bright floral skirt. Looking across a narrow asphalt demilitarized zone at a seemingly endless stream of Donald Trump supporters, she made the classic peace sign with her left hand while shouting the slogan on the blue placard she clutched in her right: "Love over hate!"

She also held a few tiny flower buds at the end of her fingertip. As I'd guessed, she told me the gesture had been inspired by the iconic 1967 photo of an anti-Vietnam activist sticking a flower pedal in the barrel of a soldier's rifle outside the Pentagon. That famous maneuver was arguably easier than a modern protester like Renner finding common cause with the Trump counter-insurgency.

"I want to wait for the right person to scream something really horrible at me so I can forgive them," Renner told me under a brilliantly blue April sky, a couple of hours before the GOP frontrunner brought his "Make America Great Again" tour to the Chester County campus.

Absolution never came, although God knows there were opportunities.

"I'm a Mexican, and I'm voting for Trump!" a man soon yelled at Renner from across the street. "My mother came her legally -- legally!!! She busted her ass!" Soon the crowd behind the man was chanting "Build the wall!  Build the wall! When Renner and some of her neighbors on the anti-Trump side of the street shot back with "Build bridges, not walls!", a voice echoed from across the chasm: "Kill all ISIS!" It went down like that for hours.

With the Pennsylvania primary just hours away, the 4,000 or so Trump partisans who stood on line for as long as eight hours and actually got inside West Chester's hoops arena to hear the billionaire's stump speech missed the real show this afternoon. The intense drama was out here on the streets -- 500 or so mostly student protesters and as many as 4,000 more turned-away and flummoxed Trump ticket-holders, facing off, separated only by a narrow ribbon of asphalt and a thin blue line of police.

The unbridgeable grand canyon of Donald Trump's America.

And for all I know they're still out their yelling at each other, hoarse and barely hearing what's being shouted across the void.

When you're a writer, some days you stare at the keyboard for hours in desperate need of a metaphor. Some days, the metaphors hit you over the head like a 2-by-4 -- this great American fault line that tore down the middle of the normally sleepy Church Street. Donald Trump didn't create this fissure. That took decades of erosion of middle-class living standards and political trust, hammered again and again by the culture wars that the hundreds on the east side of Church Street call racism and sexism and homophobia and the hundreds on the west side call "political correctness."

Trump -- with his slashing words and endless reality-show plot twists -- is the flood that fills the great American chasm with its baptism of anger and passion and a crazy kind of catharsis that, at least for the people on both sides of Church Street that I spoke with today, surpasses all understanding or explanation.

This wasn't quite the scene I'd expected to see. Ever since the bizarro Summer of Trump in 2015, I'd waited for his show to hit Philadelphia. But he never made it any closer than the far western fringe of the suburbs, and some things had changed by the time he got here. Peak Trump feels over and maybe the perfect spring weather was a kind of soothing balm. Yes, folks were passionate and divided -- but thankfully non-violent. Police reported only one arrest, of an anti-Trump protester -- even after thousands of ticket-holders who'd waited several hours in a line that snaked for about a half-mile around campus were denied admission at the end of it all.

Over the last seven years, I've written in depth about the two social movements -- the Tea Party and Occupy Wall Street -- that were the ancestors, respectively, of the west and east sides of Church Street. What struck me were how America's common threads -- the lack of opportunity for the middle-class, too much outsourcing and too much student debt, a political system hijacked by billionaires -- led people in radically different directions. Usually at a big rally or protest, people had a backstory to tell me -- but not today. The threads of narrative have dissolved into an episode of "The Jerry Springer Show."

Most of the Trump supporters wouldn't even give me their name. One 29-year-old West Chester man, a star-spangled kerchief tied around his head, told me he was drawn to Trump because "his lack of political correctness, just speaking his mind, was pretty awesome" -- but he insisted he remain anonymous because he feared any association with The Donald would kill his chances of getting into law school.

I got the same riff from a retired businessmen who serves on a non-profit board and doesn't want his Trump support made public. He did tell me that "I don't know how the Black Lives Matter people feel disenfranchised. I don't know how many pay tuition. I don't know how much more [President] Obama can do to support them."

I expected to be rebuffed when I approached 76-year-old Dolly Cacciutti of Gladwyne, wearing one of those pink Eagles caps and a T-shirt from Martha's Vineyard. After a couple of monosyllabic responses, I was about to bail on the interview when I asked her what she hoped to hear from Trump on the long-shot chance that she actually made it inside, and her eyes suddenly lit up with fire.

"I want to hear him tell people, 'Get out of here!'" She laughed, loudly, and then she said it again with even more gusto -- "Get 'em out of here!"

That's what it's mostly about, isn't it. I didn't hear a lot about policy from the Trump partisans, unless you consider "Build the wall!" to be a white paper -- just some pablum about leadership and a lot about telling it like it is, that "lack of political correctness." That's how Trump opened the floodgates of resentment until I watched it cascade down Church Street today in a sea of enraged humanity.

The crazy part is that no one out in the overflowing streets even saw Trump come or go, not one tiny orange glint, or had any awareness of when The Donald spoke or what he had to say. Just the aura of his presence somewhere on the WCU campus was enough to set off the whole doggone place. I watched angry people giving the finger and chanting everything from "USA! USA!" to "Leave our campus!" to words that can't be printed in the Daily News (yes, those still exist) and trying to debate immigration policy as much as any debate can be held by screaming over the heads of cops in riot helmets.

Around 5 p.m., when Trump was racing out of West Chester but nobody on Church Street was backing down, I heard someone grumbling about the protesters while I stood on The Donald's side of the asphalt.

"They're going to 'choose love?'" he said of the protesters. "What the hell does that even mean?"