In this city of monuments and power - in which civilian authority is paramount - we are witnessing something extraordinary.
Throughout the night, I watched heavily armed troops taking up position at strategic locations across the city.
It was more banana republic, than America.
They were a mis-match of military forces, many refusing to answer my questions about which agency or military unit they belonged to.
A lot of protesters here are curious about how this is being policed, are you with the military or with the police?
But they had the weaponry for Fallujah, even if they were patrolling the nation's capital.
At the majestic and iconic memorial to Abraham Lincoln - the very president who emancipated America's slaves - protesters gathered demanding racial justice.
They were instead confronted by rows of police and soldiers.
This is a city that hasn't seen such disturbing images since the 1960s.
Protesters and soldiers are suddenly face-to-face on American street corners.
I watched as activists and troops confronted each other.
Their exchanges were only verbal, but it underlined why soldiers should not be used as police officers.
It was a tense and ugly moment.
A mile away at the White House, the demonstration was the largest and most impressive yet.
There was greater diversity than ever before.
Washington Correspondent Robert Moore on where the protest movement could go next:
For the first time, it was a majority white crowd.
A new security fence has been erected, but that only served to fuel the frustrations.
And the protesters' demands are increasing too - this is no longer only about police brutality.
It isn't even about George Floyd anymore.
The protesters want change and economic equality.
They want radical reform to American politics.
They want accountability.
Long after the curfew was imposed, I was outside the White House and the protesters hadn't left - they were happily defying the mayor's orders.
It is our city, they told me, not Donald Trump's.
The anger is not dissipating.
The President's description of the activists as anarchists and violent criminals has served to infuriate people and exacerbate the tensions.
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