The supreme court has delivered a comprehensive demolition of Boris Johnson’s government and its handling of Brexit. The unanimous judgment of the 11 justices, announced by Lady Hale this morning, amounts to a root and branch rejection of the prime minister’s attempts to rule without parliament, to take Britain out of the European Union by 31 October without a deal, and to contrive a premature general election. The judgment was incisive and without any waffle. It was very consciously written in the best tradition of British constitutional law, of which parliamentary sovereignty is the foundational rock.

The immediate effect of the judgment is devastating for Johnson. It is expressed so cogently and unambiguously that it will be difficult for him to wriggle out of it – even though he is certainly foolish enough to try. Parliament will surely be recalled on Tuesday – since, as the judgment said, it has not been prorogued in the first place. Johnson’s efforts, to the extent that they exist at all, to negotiate a new or tweaked deal with the EU will be held up to the light. And, since Johnson spectacularly lacks a majority in the House of Commons, it is likely that the cross-party efforts to shape Brexit will be redoubled.

Pressure on Johnson to quit will surely be central to the way this all plays out in the coming days

Johnson’s own position as prime minister, along with those of his legal advisers (including the attorney general) and that of his 10 Downing Street advisers (especially his key strategist Dominic Cummings) must also be in question. It is possible that Johnson will throw Cummings to the wolves, to make him the fall guy for the catastrophically inept and illegal strategy that he has been following.

Pressure on Johnson to quit will surely be central to the way this all plays out in the coming days. His opponents, therefore, absolutely need to agree on the form, composition and, above all, the leader of any government that could replace him. If the court’s ruling means anything for politicians, it is that trying to govern as if you have a majority when in fact you do not is impossible. The belief of the hard-right Tory Brexiters that a party coup against Theresa May in a hung parliament would enable them to get their way by electing Johnson lies shattered. They need to learn the lesson very fast. Militant remainers will have to face the equivalent lesson, too. One notable consequence of the judgment, not to be overlooked in the other excitements, is for the Union. By not overruling the Scottish court of session decision on Johnson’s actions, the supreme court has upheld Scottish judges against English ones, and has removed a potential source of grievance for the SNP against “London judges” if the ruling had gone the other way

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The court’s decision has immense political immediacy. But it is also a landmark ruling in a much wider sense too. After this, it seems inconceivable, save in very restricted circumstances indeed, that prerogative powers of any kind can be exercised in any field without parliamentary authority. The power to prorogue parliament has now followed, in effect, the power to make war and to make treaties. All were once prerogative powers exercised in the past by ministers on behalf of the crown, but without parliamentary scrutiny. That is no longer possible. The process that began in the court of appeal in the 1960s under Lord Reid – the development of judicial review of public law – reached its ultimate and triumphant goal this morning.

Constitutionally, this is a magisterial landmark in the assertion of parliamentary sovereignty against the residual power of the crown and ministers. But it also bolsters parliament against all the other forces that claim to have higher authority too – from referendums to the tabloid press to the crowds in the streets.

Whether that is sustainable in an era in which parliament and MPs are held in such low regard, in which the political parties are so fragmented and partisan, and in which the electoral system that creates the sovereign parliament is so slewed in its effects, has to be in doubt. The supreme court did not just sound the trumpet over a failed prime minister. It did the same over a failed constitutional order.

• Martin Kettle is a Guardian associate editor and columnist