Britain’s The Economist is renowned for its measure, sobriety and understatement. So when the lead editorial in its 16 March 2019 edition solemnly announced that ‘the country is lost … it is a laughing-stock’, clearly something very serious had happened. Given Britain’s legacy in the near ubiquitous Cavendish cultivar—Joseph Paxton won the Royal Horticultural Society prize for it in 1835—Britain might at last lay claim to the title of the world’s first banana monarchy.

The economic, political and social consequences of the Brexit shambles have been well documented, not least of all by The Economist over many months.

Major financial institutions are relocating to the continent, car factories are downsizing or relocating, while continuing austerity measures are widening the inequality gap and narrowing the prospects for an economic upturn.

The poverty of Prime Minister Theresa May’s leadership, to say nothing about her abysmal record in both domestic political manoeuvre and international negotiation, is stark. Even starker is the prospect of Scotland’s secession from the United Kingdom, surely an unimaginable price for arrogance and hubris. And for as long as Jeremy Corbyn continues to play Punch to May’s Judy, the Labour Party offers no real hope of salvation.

This may all look like a ‘Westminster bubble’ writ large.

But in an important strategic sense, the social consequences of the Brexit fiasco may prove to be the most dangerous, since they erode one of the central pillars of long-term national security. For, along with economic strength founded on sustained prosperity, national cohesion founded on equity and inclusion is a sine qua non of a state’s ability to defend itself against both external and internal threats. As Carl von Clausewitz hypothesised and Winston Churchill demonstrated, defence is the stronger form of warfare because it brings the nation together in common purpose. Divided and demoralised however, a nation’s vulnerability is exacerbated.

The United (but for how long?) Kingdom seems to be succumbing to a kind of autoimmune disease, its vitality eroded from within as its political leaders indulge in what Matthew d’Ancona described as ‘a panorama of snivelling self-interest, squirming caucuses and abject tacticians posturing as statesmen’. Britain is rendering itself strategically irrelevant.

The threat to the union is real and increasing. The parallel acts of parliament of 1707 and 1800 that established the legal status of the United Kingdom are under challenge as Scotland contemplates separation to pursue its own economic and political future as part of Europe, and Northern Ireland contemplates a borderless and integrated future with Eire that Brexit would preclude.

While some might consider a political integration of Northern Ireland’s Orangemen with the Republic of Ireland’s Catholics as fanciful, the short-term victories of the Democratic Unionist Party in manoeuvring May into a series of ill-conceived border controls and customs arrangements may well generate exactly that outcome. Sectarianism might thrive on poverty, but poverty has the knack of eroding faith.

Even more threatening to the survival of Great Britain as we know it is the complex of divides that now gnaws away at the nation from within: the divide between the wealthy elite that governs and the poor suburbanites who are governed; the divide between the affluent south and the hard-up Midlands and north; the divide between the young and the old; the divide between the Anglo-Celtic ‘little Englanders’ and the immigrant communities; the divide between the Europhiles and the Eurosceptics that permeates both the major political parties; and the growing divide between those who support a thriving and engaged democracy and those who have succumbed to a cynical and disengaged fatalism.

If the early results of European and North American analysis of cyber interference in political campaigns are anything to go by, Britain’s internal divisions make it a ripe target for exploitation by its anti-democratic adversaries. And the combination of alienation, apathy, cynicism, fatalism, indifference, issue fatigue and hopelessness renders it even more vulnerable.

The entire Brexit fiasco is one of the greatest self-inflicted wounds in British history, a strategic catastrophe entirely due to abysmal leadership on the part of two prime ministers and an opposition that is out of touch with itself and its voting base. Britain deserves better. The question is: how can the situation be retrieved?

The decision by the EU to give May only a limited time to obtain the agreement of the Commons almost certainly means that she will fail in that task, and that she will have to resign. While the cast of potential leaders offers little hope of a political adult taking charge, May’s resignation would provide the circuit breaker that could allow the UK government to take the entire issue back to the people. An informed second plebiscite on the matter would at least display confidence in the power of a democratic popular choice, as distinct from a continuation of the divisive infighting that has characterised the whole Brexit mess.

Failing that, the United Kingdom is doomed to dissolution, and Great Britain to the strategic insignificance that two major 20th-century conflagrations failed to deliver.