In the event, it wasn’t even Westland-lite: a dim echo of Michael Heseltine’s theatrical exit from the government 32 years ago. Having pre-briefed to the press his intention to demand £100 million a week extra for the NHS at yesterday’s Cabinet meeting, Boris Johnson did not, it appears, mention such a figure.

Still less did he convey the menace of a man on the brink of marching from the top table of government. Instead, the Foreign Secretary had to listen as he was chided by his senior colleagues for breaching the most basic conventions of collective responsibility.

What was billed as a face-off over principle became a ticking-off over protocol. Or, to quote Theresa May’s official spokesman, “the Prime Minister and a large number of ministers made the point that Cabinet discussions should take place in private”. No extra cash for the health service was forthcoming and Johnson remains in post: scarcely the swaggering defence of high principle made by his erstwhile mentor over Westland Helicopters in 1986.

What Johnson does share with Heseltine (whom he succeeded as MP for Henley in 2001) is a taste for the grand projet. His decades-long, stop-go Tory leadership campaign has been punctuated by the announcement of many great schemes: the now-defunct plan for a garden bridge over the Thames; “Boris island”, his proposed estuary airport; his suggestion last week for a “Boris bridge” across the Channel (quickly dismissed by No 10); and, since the EU referendum in 2016, his insistence that Brexit will translate into a cash bonanza for the health service.

As Dominic Cummings, the strategic mastermind behind the Vote Leave campaign, has argued, the claim that the NHS would be better off by £350 million a week outside the EU was absolutely central to the outcome of the vote: “Would we have won without £350 million/NHS? All our research and the close result strongly suggests no.”

Yet the very centrality of that pledge to the Leavers’ case is now their greatest vulnerability. Johnson, who is sensitive to the prospective judgment of posterity, knows that history will not be kind to the champions of Brexit if the health service does not receive a substantial dividend from the colossal upheaval of Britain’s departure from the EU.

The mystery is why they believe that it will. Last November’s Budget was overshadowed by the sharp downscaling of future growth projections by the Office for Budget Responsibility. Tariff costs, inflation, slower growth of imports and exports, investment deterred: for the foreseeable future the most probable outcome is that Brexit will yield a net fiscal loss. Certainly those who think that a fat cheque is on its way to the NHS from Brussels can, to borrow Johnson’s own phrase, “go whistle”.

The Foreign Secretary’s supporters insist that he is battling to persuade voters that Conservatives care about the health service, and to prevent Jeremy Corbyn’s full conquest of electoral terrain that is historically Labour’s. It is true that, as David Cameron observed when he became party leader in 2005, the Tories have always had to combat public suspicion that the NHS is unsafe in their hands. It is also true that the health service badly needs more cash.

Yet little is achieved — beyond newspaper headlines — by grandstanding assertions that Brexit will square the funding circle. For a start, such populist rhetoric obscures the complexity of the problem.

In the short term, the health service requires more money, fast, to address its immediate crisis of capacity. At the same time it would be deeply irresponsible of the Government to squander now the gains of nearly eight years of fiscal conservatism. Yesterday the Office for National Statistics announced the lowest year-to-date public sector net borrowing since 2007 — a vindication of a hard-won strategy to restore economic stability.

The May Government lives only in the sense that it has not died. It has no direction, purpose, or discipline Matthew d'Ancona

It is becoming perilously commonplace to take these gains for granted. Yet, as Philip Hammond signalled before yesterday’s meeting, this is no time for fiscal incontinence: “Mr Johnson is the Foreign Secretary. I gave the Health Secretary an extra £6 billion at the recent Budget and we will look at departmental allocations again at the spending review when that takes place.” In other words: stick to quoting Kipling and get your pushbike off my lawn, Boris.

Distinct from the question of an immediate cash injection is the much greater issue of the long-term sustainability of the NHS and its integration with social care — a process foreshadowed by Jeremy Hunt’s welcome promotion to oversee both. This will certainly entail fresh sources of revenue, probably involving the taxation of wealth.

But it will also require radical reform based not on yet more bureaucratic structures but on a shift of emphasis towards prevention of illness, early intervention, and a clinical strategy that is mostly enacted outside hospitals. Increasing longevity, the march of medical science, and the total inadequacy of social care as presently configured present challenges far deeper than any winter crisis. This is the work of a generation, not of a pre-briefed soundbite. It is as great a task as the creation of the NHS 70 years ago.

What yesterday’s Cabinet fiasco demonstrates, of course, is that the May Government is intrinsically unsuited to such an undertaking. Frozen in the aspic of its own uncertainty, it does nothing more than continue to exist. It lives only in the sense that it has not died. It has no direction, purpose, or discipline.

Johnson’s antics are but a symptom of a much deeper pathology, a running commentary on the conspicuous absence of leadership in No 10 and the Tory Party’s apparent inability or unreadiness to do anything about it. The Foreign Secretary acts this way not only because it is in his nature, but — much worse — because he can.