An interesting hypothetical exercise is to imagine what would have happened if Chuka Umunna’s sudden publicly-expressed desire – after nearly two years of a “principled” boycott – to return to Labour’s front bench had received a positive response.

Would he have become the shortest serving Shadow Cabinet minister in history? Given the length of front bench tenures under Jeremy Corbyn’s leadership, that’s quite a record to beat. But still, old Chuka would have given other contenders a run for their money.

There are two fascinating – and potentially era-defining – aspects to last night’s drama, which resulted in the departure of four Labour MPs from the front bench after they defied the whips on a vote in the Commons. The first is the apparent surprise some observers felt at Corbyn’s heavy-handed response to the rebellion, in which a total of 49 Labour MPs voted for Umunna’s amendment to the Queen’s Speech expressly supporting Britain’s continued membership of the single market after we have left the EU.

Given the apparent unity that has pervaded the Parliamentary Labour Party (PLP) since Corbyn’s better than expected performance at the general election, the Labour leader will have come under some pressure to ignore the rebels’ actions for the sake of public perception. And he would have been wrong to entertain that advice. Yes, he is well known for having voted against his own party whip hundreds of times, and he showed few reservations about walking through the lobbies side by side with the Conservative Party to oppose Labour policy over many years.