It is tempting to think the crisis enveloping Labour over Article 50 was inevitable. Many have suggested that, faced with the referendum result, Jeremy Corbyn had little choice. With 94% of Labour MPs having campaigned to remain yet two thirds of the party's constituencies voting to leave, a different leader could have done little else.
Yet, having now signed a blank cheque for a prime minister threatening to tear Britain out of the EU and stake the future of the economy on a protectionist and sociopathic American president, Labour's position could scarcely be weaker or more uncomfortable.
European unity will prevent Theresa May getting the sort of deal she has raised expectations of. There is ample reason to believe a trade deal will not be ratified until the early or mid-2020s. Even a transitional deal will prove extremely difficult, given the divergent interests of the other 27 countries. For Labour, being seen to endorse this ill-fated plan doesn't just represent bad policy – it is terrible politics.
Another approach could have been taken: one which, even with Corbyn at the helm, could have held the party together, and positioned Labour as a genuine alternative as the Brexit fantasy begins to unravel.
This would have begun back in the autumn, with the shadow cabinet and PLP coalescing around a clear position, spoken of publicly only as one of a number of options under consideration: continued membership of the single market with immediate application of an emergency brake on immigration, and a drive for serious reform to free movement.
Corbyn would have made high-profile visits to Brussels, Berlin and Paris, meeting key figures on the European left. In December, with Theresa May lacking either a plan or any allies on the continent, Labour would have hosted a London summit of socialist party leaders. Pictures of Corbyn alongside European presidents and prime ministers would have helped re-cast him as relevant and determined to get the best deal for Britain.
The contrast with the unhelpful insults coming from the Tory cabinet would have won plaudits. And the Government would have begun to see Labour as useful in securing the best deal; political capital Corbyn could have banked when pushing amendments to the Article 50 bill.
A disciplined media strategy would have helped keep the focus relentlessly on the Tories. Speeches lauding the "enormous opportunities" of Brexit would not have been made, and unhelpful remarks from shadow cabinet ministers would not have been tolerated. Labour would have refused to be drawn on whether it would "frustrate" the triggering of Article 50. The notion that any party would commit to voting in favour of a piece of legislation it hasn't seen would have been dismissed as absurd.
When May finally spelled out her plan in January, Labour would not have given the impression it endorsed it, but spelled out that it risked a train crash Brexit, and that by ruling out membership of the single market and the customs union before the negotiations, the prime minister had caved in to extremists.
Labour would then have fleshed out its own approach. This would have been attacked, but its by-now sharply honed message would have had the support of much of the PLP, business and the public. Having set the narrative about what was achievable, "hard Brexit" would have remained as unpopular as it was in the weeks after the referendum.
The accusation that it is unrealistic to aim for membership of the single market and reforms to free movement would have been met with the response that the Tories are not being ambitious.
The charge that staying in the single market would hardly constitute leaving the EU could have been easily rebutted. Tory Brexiteers previously campaigned for the 'Norway model' themselves, rightly pointing out that the EFTA court is not under the jurisdiction of the ECJ and that many of its rulings are not binding.
So Labour would have voted with the government at second reading of the Article 50 bill, but explained that its support was conditional on winning a key concession. Its central amendment would have mandated that, before Article 50 could be triggered, Parliament must first vote on whether Britain should leave the single market.
The vote on this amendment would have carried Lib Dem and SNP support but Labour's whips would have ensured beforehand that it would be narrowly defeated (thereby avoiding a disastrous general election). However, with moderate Tories by now seeing Labour as a useful and influential ally, and the government under pressure to offer genuine concessions to coax back their rebels, crucial additional amendments could have been won.
Corbyn would then have announced that, having failed to get assurance that Britain would not crash out on WTO terms, he was whipping his MPs to abstain at third reading. Not every MP would have obeyed, but the shadow Cabinet could have been held together. MPs from heavily leave constituencies could have returned to their constituents saying they voted for Brexit (just a different type) and didn't block Article 50.
Those from pro-Remain constituencies could say they fought for a soft Brexit, but refused to back the government's dangerous plan. They could have reminded their electorate that Labour couldn't have blocked the bill, given the Tories' majority.
The party would undoubtedly have suffered some losses in the short-term. But it would have established a counter-narrative for the public to buy into as the reality of Brexit kicks in: that the chaos and economic pain is not Brussels' fault, it is the Tories'. Having fought for a far less damaging course, Labour would have earned itself the right to be listened to in the months and years ahead.
Instead, the party increasingly seems incapable of speaking to either the 48% or the 52%. This was not inevitable, but the result of a sustained lack of strategy and political leadership.
The tragedy, quite apart from Labour's woes, is that the country is being denied effective opposition to a government pandering to political arsonists on both sides of the Atlantic.
The author is a member and former employee of the Labour party who wished to remain anonymous.
The opinions in politics.co.uk's Comment and Analysis section are those of the author and are no reflection of the views of the website or its owners.