It was, no matter where you stood, an astounding day.
The man of the moment was no longer Donald Trump the reality TV star, or Donald Trump the real estate baron-turned-politician.
He was Donald Trump, president of the United States.
If they ever bring back the $10,000 bill, his mug will be on it.
Friday's inauguration was for some a dream come true, and for others the beginning of a four-year migraine.
Convention and civility were trampled on for more than a year during the campaign, we're as sorely divided as ever, and Trump's inaugural speech was vintage Trump.
The polarizer-turned-president indicted the political elite he had just joined.
"We will no longer accept politicians who are all talk and no action," he said to cheers.
So here we go. Trump made promises in his campaign and in his inaugural speech. Big promises. Lots of promises.
That was the easy part.
We're about to find out if the guy who was all talk, with a stable of scapegoats for whatever ailed the nation, can deliver.
But let me back up to the hours before Trump took the oath.
I started the day at McPherson Square, base camp for protesters. As a native of California, whose clean air regulations already appear to be under threat from a Trump Cabinet nominee, I wanted to hear people out.
The first person I approached happened to be a San Diego lawyer named Lisa, who was demonstrating in support of the Center for Biological Diversity but didn't want to give her last name because her views are hers and not her firm's. Californians, by the way, are all over D.C. as leaders of the resistance. My plane out of LAX was loaded with people on their way to Saturday's women's march.
"I care about climate change in general, and loss of habitat and public lands," said Lisa, who worried that based on comments from Trump and his inner circle, environmental protections won through years of hard work could be at risk.
"We'd be foreclosing on our children's future," she said, mentioning the withering of the Great Barrier Reef. "We just had the hottest year on record in 2016, which superseded 2015, which superseded 2014."
The next people I encountered — Alex and Andrea Ventura — were from Atwater Village. When I asked what issues they were concerned about, Alex said: "Where do you begin?"
The new administration, they said, seems out of step with D.C., a progressive city with lots of bikes, hybrid taxis and science museums. They'd been to the Natural History Museum, where there's an exhibit on climate change.
Maybe Trump can take the oil tycoons and climate deniers in his inner circle on a field trip.
"His pick for EPA sued the EPA, and he's supposed to inspire the staff?" Alex said. That's the guy, Scott Pruitt, who questioned California's authority to impose tougher auto emissions.
So the demonstrators had plenty to work with, and they made their presence known across the nation's capital Friday, many of them stationed along the parade route.
A Trump supporter on Pennsylvania Avenue passed a demonstrator holding a sign that said "Not My President."
"Yes he is," the Trump supporter said.
That's what the history books will say — and Trump's backers were as gung-ho as his detractors, as if he were the second coming.
In more ways than one.
"We believe this is God's will," said Sharon Patrick, who was with her buddy Amy Jemery. They were convinced Trump would accomplish more in short order than President Obama did in eight years.
Ron Potts, a college student from Florida, said Trump would "unify us" after years of divisive leadership. You were made to feel like a racist, he said, if you didn't embrace Obama's policies.
His mother, Carol, said Trump had appealed to her early on because he financed his own campaign and wasn't beholden to anyone — and he was clever enough to get "billions of dollars' worth of free press."
She said sanctuary cities should have federal dollars shut off and thinks the dream of a better life died under Obama and that Trump inspires hope.
But he promised a lot, I said, and was short on details. What if he doesn't come through?
"Then we'll vote him out," she said with conviction.
Even some Trump foes said that he had heard and spoken to and connected with people who felt left out.
I saw it a little differently. I think he told them what they wanted to hear.
I'm reminded of my trip to the Orange County Fairgrounds to watch candidate Arnold Schwarzenegger drop a wrecking ball on a car. Then as governor, he scaled back the car tax — a $4-billion tax break that immediately created a $4-billion deficit he couldn't dig out of.
The act wore thin when he didn't deliver, and the lesson was an old one: Beware the politician with simple answers to complicated problems.
Trump, to his credit or detriment, has made huge promises and provided scant detail. Affordable healthcare for all, better jobs for all, and the extermination of radical Islam, to name a few.
He's got a lot on the line, and so do we.
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