Jeremy Corbyn simply does not have what it takes to be prime minster

Policies are the staple of political debate, but every so often, the focus shifts from 'what is to be done?' to 'who should be in charge of doing it?'. The Brexit vote has sparked a cascade of leadership contests in the UK: David Cameron and Nigel Farage have resigned, and Jeremy Corbyn hangs on by a thread. Twenty of Corbyn's shadow cabinet resigned, and he lost a subsequent vote of no confidence by 172-40. He is now embroiled in a contest that has raised questions about his character and capacity for leadership.

Despite all this, there is much to be said for Corbyn. Following an unexpected election loss a year ago, he took over a dispirited party. With a clear and coherent set of values, firmly and sincerely held, he reenergised the Labour party faithful, and attracted thousands of new members with it. He is a compassionate and committed conviction politician who obviously has the public good at heart.

But the most incisive comment on his leadership came from Hilary Benn, former Shadow Foreign Secretary. Having just been sacked from the front bench on the grounds that he could no longer support the party leader, he explained his reservation about Corbyn in these terms: 'He's a good and decent man, but he is not a leader, and that is the problem'.

Ultimately, Corbyn has fallen short as the leader of the opposition, and his record does not suggest he would excel as prime minster. The leader of the opposition is responsible, first and foremost, for holding government to account. This requires cooperation from parliamentary colleagues to form an effective and unified shadow cabinet. While popular with the grassroots, he was never the parliamentary party’s choice, and he has failed to win them over. Indeed, following the Brexit vote, he had difficulty filling his shadow cabinet, and ultimately reduced it from 31 to 25 and promoted to the front bench several with scant political experience.

Leaving aside concerns about his ability to organise an effective opposition or government-in-waiting, Corbyn has not shown that he has the character for leadership on this scale. Specifically, he appears to lack three virtues the UK needs from its leaders at this critical juncture:

1. Judgement: Political leadership, above all else, requires judgement in decisionmaking. The formal rules by which political leaders are bound rarely settle what they should do to address the problems they face. Corbyn has done little to suggest that he possesses the required wisdom. Nowhere was this more evident than his calling for Article 50 to be invoked only hours after the Brexit decision. This was a baffling error of judgement, surely betraying a failure to understand the delicacy and complexity of what lay ahead.

2. Political Skill: Brexit may mean Brexit, but quite what Brexit amounts to is yet to be determined. This next period of British politics requires a leader who can persuade, bargain, and compromise skilfully. One of Corbyn's party colleagues, Stephen Kinnock, put it best: 'now more than ever what our party and country needs is a leader who is a persuader, not a protester.'

3. Tenacity: The UK needs a leader with the tenacity to see all of this through to its end. Corbyn’s unconvincing contribution to the ‘Remain’ campaign precipitated the revolt among his front bench. One suspects he was a reluctant advocate of Remain, and this shone through in his less than full-blooded commitment to the cause. But having chosen a side, he showed little to suggest that he can deliver on his commitments. Vision is important, and all too rare, but the journey from policy document to real world practice is neither clean nor easy.

The challenge of negotiating Brexit requires higher levels of judgement, political skill, and tenacity than before. Corbyn would be at his best leading a protest movement or a small but passionate party that occupies the safe waters of opposition, where political convictions need not be reshaped to fit political possibility. None of this settles the question on Corbyn, however, for politics is about finding the least imperfect path. And perhaps most worrying of all is that, in Owen Smith, Labour's alternative is an unknown quantity. The absence of a credible opposition and the dearth of experienced, skilful politicians from the Left is not a concern just for the Labour Party, it is a concern for the British public, and, with our fate so closely tied to theirs, it is a concern for the Irish public too.

John William Devine is a political philosopher who works on Ethics in Public Office. He has taught Philosophy at King’s College London and the University of Birmingham.