Britain’s long-running Brexit saga has thrown up a new argument: Does Prime Minister Boris Johnson have a cunning plan for conjuring up a new and improved exit deal, or is he just dragging the UK over the “no-deal” cliff edge? The highest court in Scotland last week ruledJohnson’s prorogation of Parliament to be unlawful, and the House of Commons forced him to release the gloriously named “Operation Yellowhammer” documents, which contained highly damaging official assessments of the catastrophic impact of a no-deal Brexit. The latest divisions within the Conservative Party — including the ouster of 21 MPs who opposed Johnson’s approach to Brexit — appear to be of historic consequence. As the UK Supreme Court prepares to adjudicate on several cases that have been brought against the Johnson government, it finds itself being drawn into a political role similar to that of its American counterpart. On one level, Britons may be dismayed by this. On another, there will be deep relief that, despite the current assault on Britain’s uncodified constitution, there are at least still fair-minded judges to stand up for it. These new points of debate emerged amid scenes of late-night mayhem in the House of Commons before Parliament was summarily closed on Sept. 9. During those surreal hours, when members of the House of Lords (usually a pretty sedate place) broke a rare filibuster by government loyalists, I ran into my fellow peer Michael Dobbs, the author of “House of Cards.” We wondered what was left for his writing now that the facts of political intrigue have so outstripped fiction. The villain protagonist of his books, Prime Minister Francis Urquhart (or US President Frank Underwood in the American TV series), seems like a sober and respectable political operator compared to many current UK political leaders. The question now, of course, is whether Johnson has a plan — or at least a compass — for navigating the chaos he helped unleash. A best guess depends on where one sits, and how one is accustomed to thinking about uncertainty. Those rationalists who are in the business of assessing political and financial risk seem to think that Johnson does have a plan. After exhausting his opponents and throwing the country into turmoil, he will make a last-minute lunge back to the center, mustering a coalition of relieved Tories and Labourites behind a modified version of former Prime Minister Theresa May’s thrice-rejected deal. In this scenario, Johnson might lose part of his right wing — the European Research Group — but he might win over a sufficient number of Labour MPs and Tory rebels. All would be relieved at this point just to avoid a sudden, hard break from the EU. His key challenge is finding a face-saving way around the so-called Irish backstop, and he does seem willing to contemplate a single Irish market, at least for agricultural goods, as long as the agreed nomenclature avoids acknowledging that, for all intents and purposes, it leaves Northern Ireland in the EU single market. But the thinking among MPs and the chattering classes is different. Here, most see Johnson not as a man with a plan, but as a blundering bull in the Westminster china shop. By closing off his own options for compromise, and by ignoring Parliament’s instructions, Johnson is hurtling toward either a no-deal exit or the fall of his government. His one lifeboat — if he can reach it — is a general election, which he would try to frame as a “People versus Parliament” contest. Johnson himself most likely has no idea how this will end. Since his initial burst of braggadocio, his political opponents have sapped his momentum. His consigliere, Dominic Cummings, has become the story, with the media gleefully casting him as the Rasputin of Johnson’s court. Reality is outstripping fiction once again: The real Cummings is proving to be even more demonic than his fictional version, played by Benedict Cumberbatch in Channel Four and HBO’s 2019 feature “Brexit: The Uncivil War.” The financial and policy classes believe in rational decision-making because that is how they operate, but politicians (now more than ever) tend to rely on the powers of emotion and instinct. If Johnson lacks a plan, he is in good company. Labour has tied itself in knots promising to renegotiate a better exit deal, even though its best leaders would then campaign against that very deal (in favor of “Remain”) in the event of another referendum. Reason is not welcome at Westminster. Still, plan or no plan, the brinkmanship on all sides could facilitate a deal. Like exhausted prize fighters, the warring factions may embrace each other just to stay on their feet. But this would surely lead to a terrible deal. It would have to be cobbled together at the Oct. 17 meeting of the European Council, where European leaders are growing increasingly frustrated with the entire process. Moreover, Johnson has already disbanded the civil service team that led the previous negotiations. Any new agreement will be May’s old deal with a few bells and whistles, and it will push the real issues down the road rather than ending the Brexit debate. That show has years to run. Most see Johnson not as a man with a plan, but as a blundering bull in the Westminster china shop. Mark Malloch-Brown With the UK having worked itself into a frenzy, rational decision-making about the future has become all but impossible. Even if the rationalists are right and a new deal emerges, it won’t have emerged for rational reasons. For better or (considerably) worse, the Brexit virus still has a deadly hold on the British body politic. A new deal would be a placebo, not a cure.