Hundreds of protesters marched in Brighton, and thousands have joined similar marches against him across the country.
But while the protest felt somewhat muted, and was not a mass outcry, it still points to how important a protest movement will be to challenge Alexander Boris de Pfeffel Johnson.
It was noteworthy because it brought together people from different political backgrounds, including the trade unions, Extinction Rebellion, LGBT activists, the Labour Party, and more.
I arrived a little late, so missed one or two of the speeches, but a core theme that emerged was how campaigners from various groups will need to stick together.
At the moment, Boris Johnson is a loose cannon, but his appointment of a staunchly hard right wing cabinet should fool no one about the direction he seeks to take.
His previous comments about Muslim women wearing burkha show he is prepared to deploy racism or any division if it suits him.
So unity is a key to challenge him, but so is a grassroots protest movement that has confidence in itself.
At Brighton today there were some signs of this, some seeds have been sewn which will grow in the months to come.
Wolfran Lohr told me his son had joined the Brighton youth climate strikes, which has inspired him to stand up and use his voice too.
Meanwhile Nikolai Brown joined the protest in her wheelchair to rightly point out that this is the second Tory Prime Minister we have had foisted upon us without a general election.
One speaker at The Level was Alex McIntyre, who has been organising Wetherspoons workers to fight for their rights and for union protections against a very Pro-Brexit boss.
He said: “Boris Johnson is a racist, sexist, homophobic bigot who does not represent any of us.”
His kind of campaign in the event of a “no deal Brexit” will be crucial to give people in non-unionised industries a voice against the bosses.
Nell Chipping from Brighton Queer AF spoke very well about Johnson’s record on LGBT rights, and is right to point out the danger the Tories now pose to rights which have been hard won for many different communities.
One speaker from the UCU union also made the age old but hugely important statement about the left, that while we may disagree about what tactics to take, the tactics are not the problem we have to focus on, toppling the Tory government is the key objective.
There have not been enough protests against the Conservatives, perhaps as Labour has tried to project an image that it is not just a protest movement, but a party ready for government.
That is Labour’s business, but the protest movement across many campaigns is vital, and should never be put in a box and stored away to the side.
It should be front and centre of any campaign for a radical government that puts people and the planet first.
In the past we have seen how protest movements can radically change politics, be it anti-war, anti-racism, or fighting against the destruction of climate change.
The Labour leadership would do well to remember the power of street protests and a movement, it could be the only thing which can halt the Tories and challenge their free-market ideas.
“We want a general election now” was one of the chants alongside “Johnson out!” on the protest today.
It felt a bit tentative, but its strength was perhaps more in the range of groups being represented on the demonstration.
Boris will probably get a honeymoon period, because for however unpopular he is with the left, he is also popular with the right.
He will seek to use this to his advantage in the forthcoming weeks to shore-up support in the Tory party and for a no deal Brexit.
It will be the task for the left to build a movement that makes his job even more of a poisoned chalice than that which Theresa May inherited.