IT is tempting to speculate on how historians will look back on Theresa May’s Brexit traumas and pass judgement on the Prime Minister.

A sympathetic chronicler could, at a push, commend her resilience, while a less friendly biographer would probably view her as an ineffectual leader who was a hostage to extremists on her own benches.

Her Government is likely to be judged as a temporary stop gap that failed to deliver a maligned version of Brexit. In a league of Prime Ministers, she would be deep in the bottom half, facing relegation.

But just as May leads the most dysfunctional Government in living memory, so too can it be argued that Jeremy Corbyn leads one of the worst Oppositions in history.

In a year in which the Tory Government has veered from crisis to disaster, and where May has been humiliated by all sides in the Brexit debacle, some opinion polls still put the Tories ahead of Labour. May’s approval ratings outstrip Corbyn’s terrible numbers.

The Tories have a plausible excuse for their disarray. The UK’s relationship with the European Union has obsessed the Conservatives for over thirty years. A sizeable number of May’s colleagues got into politics because they wanted the country to withdraw from the EU. It is the one issue on which some Tory MPs will never compromise.

Labour is not encumbered by this historical baggage and is unashamedly pro-European. The party’s members and parliamentarians overwhelmingly want to stay in the EU and would breathe a collective sigh of relief if Corbyn moved onto this ground.

Labour’s sliding scale of priorities for Brexit - get a better deal than May, force a general election or, as an absolute last resort, campaign for a second referendum - reflects the divide between the membership and the leadership.

Party sources say the obstacle to Labour adopting an anti-Brexit position is Corbyn and his loyal aides, Seamus Milne and Karie Murphy. Corbyn is a lifelong Eurosceptic whose ill-feeling towards the EU is stronger than the mild distaste for the project displayed by members of the Prime Minister's Cabinet. Deep in his gut, he feels that Brexit is an opportunity.

In ‘All Out War’, a book by journalist Tim Shipman on the craziness of Westminster politics after the referendum, the author recounted one of the hustings during the 2015 Labour leadership contest that led to Corbyn’s victory. Asked if they would rule out voting No or campaigning for Brexit ahead of a referendum on the EU, every candidate did so, apart from Corbyn. “No I wouldn’t rule it out,” he said.

Part of the blame for the paralysis at Westminster can be laid at Corbyn’s door. Given that May will not get her draft deal past her own party, and given that she is unlikely to be the person tasked with producing a radically different option, it seems obvious that any solution must involve Labour.

And yet, despite Brexit being the most important issue in UK politics since the second world war, Labour’s position appears to be to sit on the sidelines and wait for a Tory implosion to lead to a general election. It is a strategy based on the hope that some Conservative MPs are stupid enough to want to bring down their own Government.

The alternative, which left-wingers like shadow chancellor John McDonnell appear to realise, is clear. Corbyn could point to the fact that a clear majority of his voters want to remain in the UK. Labour could contrast the false promises made during the referendum with the shambles that has ensued. They could conclude, just as the SNP did eventually, that a final referendum is required.

Whatever happens over the next three weeks, the parliamentary arithmetic dictates that Brexit is no longer an inevitability. Once May’s deal dies, only two options could carry a majority in the House of Commons: a softer Brexit that would mean retaining freedom of movement; or another referendum. The first would be unpalatable to voters, while the second, if offered as a choice between a harder Brexit or remaining in the UK, would be an easier sell.

Labour’s choice is between sitting passively in the back seat, or grabbing hold of the steering wheel and, to use a well worn phrase, taking back control. Otherwise Corbyn, like May, could become another casualty of history.