13 June 2019updated 08 Jul 2021 12:29pm

Chuka Umunna joins the Liberal Democrats in a coup for Vince Cable

LONDON, ENGLAND - MARCH 05: Independent MP Chuka Umunna speaks to the press after a meeting at the Electoral Comission with other members of the Independent Group of MPs on March 5, 2019 in London, England. The Independent Group consists of eight former Labour MPs and three former Conservative MPs who split from their respective parties last month citing a range of issues. (Photo by Jack Taylor/Getty Images)

Chuka Umunna has joined the Liberal Democrats in a major coup for Vince Cable and the Streatham MP’s new party in general.

From the perspective of Liberal Democrat self-interest, the biggest problem that they and the other minor parties have is getting in the news at all, and a defector is obviously a boon to them. With the exception of the 2017 general election, when the Liberal Democrat campaign was consumed by rows over Tim Farron’s views on homosexuality and reproductive rights, the party usually gets a boost in election time for this reason. Anything that increases their prominence in off-years increases what you might call their “resting” level of support.

It also gives them a way back in Streatham, a constituency in which they made a strong challenge in 2010, were whomped in 2015 and 2017 but won in the European elections (they have also made forward strides in local council by-elections in the seat).

The benefits of incumbency and, if they are lucky, the Labour candidate, gives them a path to make the seat at least competitive again and perhaps even to win it off Labour in the right national environment.

Umunna is not the biggest prize from a constituency perspective – former Conservative MP Heidi Allen, who is also believed to be open to joining the Liberal Democrats, and privately argued for an alliance between them and her short-lived party Change UK, and Sarah Wollaston in Totnes, both hold more winnable seats. But Umunna’s proximity to both Allen and Wollaston, and his long-standing friendship with Luciana Berger, whose Liverpool Wavertree seat is well outside the Liberal Democrats’ grasp but who many Conservatives in the so-called “Bagel Belt” of north London constituencies, where the British Jewish community is well-concentrated, think could revive Liberal Democrat fortunes there, will increase Lib Dem hopes that they can tempt over those three as well in time. Allen and Wollaston, in particular, are believed in Liberal Democrat circles to be likely to follow Umunna.

Other than on the issue of Heathrow expansion, Umunna will fit well with his new party on most issues, but it is a bold decision on the former Labour MP’s part. As he himself admits, he was not one of the former Change MPs who advocated for a close relationship with the Liberal Democrats. Indeed, he thought and said publicly that the party was a finished force.

It is a particular triumph for Cable personally, who has worked closely with Umunna for a number of years. During the coalition government, when Labour and the Liberal Democrats would occasionally work with one another to defeat the Conservatives, with whom the Liberal Democrats were sharing power, Cable and Umunna were in regular contact, though the formal line of communication was between Stewart Wood, Ed Miliband’s close ally, and Jonny Oates, Nick Clegg’s chief of staff.

Umunna’s defection means that Cable will go into retirement having overseen Liberal Democrat gains of over 700 councillors, 15 members of the European parliament and one MP.