The resistance to the Johnson-Farage axis will not come from the parliamentary Conservative party. In private, MPs, who once made sure demagogues did not become prime ministers, admit that Johnson is a phoney, unfit for high office or any office. But the Tory party’s guardians no longer care. The gatekeepers are lifting the lock and urging the bullshitter to charge into the china shop.

They calculate that only an alliance between the right and the far right can ensure their party’s survival. The pact may be unacknowledged. Johnson may neutralise the Brexit party by becoming more Faragist than Farage. The Tories will take his votes and he will fade into the background. I don’t see a man with Farage’s sense of entitlement fading willingly. His friends Matteo Salvini and Donald Trump have power in Italy and America respectively. Why should Britain’s man of destiny allow the Conservatives to pat him on the head and say: “The grownups will take it from here”?

Farage more than any other politician is responsible for Brexit and feels no shame for the pain he has inflicted on the country he professes to love. He can threaten to run candidates against the Tories and let Labour in unless they recognised his greatness by making him, say, deputy prime minister. He surely wants to enter parliament in an early election and his surest route to Westminster is via an electoral alliance with the Conservatives.

One way or another, what we call “populism”, a feeble euphemism for an ideology that tolerates no constraints on the leader or his party, will soon be here. Indeed, it already is. For it is one thing for the Putinesque no-hoper Dominic Raab to say that he would suspend parliament to force through a no-deal Brexit. Quite another for Johnson, “our” next prime minister, to tell the Tory right he won’t take bypassing the Commons off the table either.

The crash that Farage and Johnson contemplate with such insouciance is as much a constitutional as an economic monstrosity. Whatever mistakes they made, no previous administration has deliberately wrecked the economy. But then no administration in the modern era has dared to contemplate inflicting economic misery without a mandate from the Commons or the electorate. You cannot say often enough that a no-deal Brexit was not on the ballot in the 2016 referendum. The 2015 white paper that spelt out the terms of the referendum did not say that no deal would follow a Leave vote, while Johnson and every other senior Leave politician promised that a free-trade deal would follow.

Populism is such a treacherous word because it implies that “the people” are in control. Farage and Johnson are proving that in the populist state the leaders are sovereign and the people get what they are given. You shouldn’t be surprised. What kind of popular democracy do you expect when the decisive voice in choosing the national leader is not the electorate’s but the voices of 160,000 Tory activists?

It was a new type of press conference where Johnson’s claque booed reporters for asking questions

What of my trade of journalism? A poor thing, you might say, and one whose deference to “Boris” has been a disgrace. But as his first press briefing showed, our next PM treats reporters who call him “Johnson” and hold him to account with a hostility he never shows to the flunkies on first name terms. Instead of being a moment where journalists questioned a politician, it was a new type of press conference where politicians who supported Johnson booed reporters for asking questions.

I could go on. An independent civil service is a check, if only a reality check, on deluded politicians. The Institute for Government tells me what I had already guessed: Brexit has produced an unprecedented rise in the number of political attacks on civil servants. One of the first acts of a Johnson regime will be to fire Olly Robbins, the prime minister’s Brexit adviser. He has become a George Soros-style hate figure on the British right: the sinister manipulator its partisans blame for the inevitable failure of their impossible project.

Once the greatest check on runaway power was the opposition. Jeremy Corbyn agrees with Johnson and Farage on the need for Brexit, however, and only queries the detail. His failure to support Remain has fractured the centre left, opening the prospect of a united right coming through the middle in a general election. In any case, look at my description of rightwing authoritarianism. It applies as well to the far left. Corbyn and his network of post-communists don’t want to stop a recession. They are “disaster socialists” who hope, as Lenin hoped, that economic collapse will turn the masses to their cause. They would happily suspend parliament to force through a radical programme and nothing in their ideology suggests they believe in press freedom or civil service independence. They won’t oppose what they yearn for.

Opposition must now be as much without as within parliament. I am heartened to see that the next pro-European march on 20 July will be the start of a full-throated defence of EU membership rather than a process argument about the need for a second referendum. Protests on the streets will not occur in isolation. If any government risks no deal, the financial markets will go wild and employers will warn staff about their jobs. MPs may act independently and reconvene away from a shuttered Westminster. It will be the greatest economic, social and political crisis of our lifetime.

Whenever you talk about the far right or left, or make comparisons with Putinism and fascism, you are told it can’t happen here. Don’t be hysterical, old chap: Johnson is a joke, Farage a pub bore and Corbyn a passive-aggressive crank. They can’t hurt us. The critics don’t realise it has never happened here before because enough “hysterical” citizens have stamped on it early and hard. We are late in the day this time around and the moment to start stamping is now.

• Nick Cohen is an Observer columnist