JUST when the Labour leadership can look to reap the political benefits of daily blue-on-blue in-fighting with the Conservative leadership contest, what happens: acrimony breaks out on the left to remind everyone just how much of a divided force the Opposition can be too.

Sir Keir Starmer, trying to mould his party into a credible, alternative government, wants to show that where there is division, incompetence and policy stagnation with the Tories, there is unity, competence and fresh ideas with Labour.

Of course, the summer strike action has proved painful for the post-Corbynite leadership because of the party’s historic ties with its trade union benefactors and given it portrays itself as the champion of ordinary working folk.

Sir Keir has made clear to his parliamentary colleagues the party’s primary task is to win the next General Election and, to that end, its front bench has to “get in the mindset of being in government”.

Read more: Time is now of the essence for Rishi Sunak

Yesterday, he insisted Labour would “always be on the side of working people” but emphasised the need for collective responsibility, having previously told colleagues: “If you’re around the Cabinet table, you have to resolve these issues, make sure the negotiations complete successfully. You can’t have a Cabinet meeting and then go out onto the picket line.”

While several Labour MPs have appeared on picket lines, Sir explained he sacked Sam Tarry as shadow transport minister for giving media interviews without the party HQ’s say-so and for having “made up policy on the hoof” – that is, that every worker should get a pay rise in line with inflation.

John McDonnell, Jeremy Corbyn’s Shadow Chancellor, accused the Labour leader of stoking an unnecessary row within the party, branding his approach a “severe mistake,” and claimed Sir Keir had “misread the public mood” on the strikes.

But he went further. Asked about calls for a general strike should Liz Truss realise her plan to ban strikes in essential services, the London MP said he was all in favour of “co-ordinated action” as this was the best way to get people a decent pay rise.

While Sir Keir will be holding his head in his hands, Rishi Sunak and Liz Truss must be punching the air; a break from metaphorically punching each other.

Last night saw the first of 12 Tory leadership local hustings in Leeds; a two-hour head-to-head. The Scottish one in Perth takes place on August 16. The new leader will be announced on September 5.

Tonight, Mr Sunak undergoes his own masochism strategy with an Andrew Neil grilling on Channel 4; Ms Truss has declined the grand inquisitor’s kind invitation, underlining she has more to lose.

Postal ballots to the 160,000 Tory members will drop next week; many will send them off quickly. So, next Thursday’s Sky News debate between the two candidates could prove vital.

Time for Mr Sunak is short. Worryingly for the ex-Chancellor, a poll of around 500 Tory members after Monday’s BBC TV debate found 50 per cent thought the Foreign Secretary had performed the best compared to 39% who thought he had done so.

It looked like an act of desperation that hours later Mr Sunak unexpectedly announced a “targeted and temporary” plan to introduce a VAT cut on fuel to “help deal with the current emergency”, saving average households £160 a year.

Understandably, Ms Truss supporters accused the Yorkshire MP of flip-floppery given it was only months ago he had opposed such a plan from Labour, arguing it would "disproportionately benefit wealthier households" and become a permanent cut.

Mr Sunak’s camp insisted the VAT proposal was in line with his pledge to help struggling households with their bills and stood in stark contrast to the inflationary £55 billion of fiscal commitments Ms Truss had made.

But having for so long denounced the “comforting fairy-tales” of Ms Truss’s tax-cutting agenda, it didn’t look good that the ex-Chancellor appeared to be following in her trail.

It was also intriguing to see how both had expressed a willingness to be in each other’s Cabinet should they fail to seize the Conservative crown themselves. Given they have denounced each other’s economic policy as “immoral”, it would be interesting to see how that works out.

In the months ahead, Labour should be greatly encouraged as all its best campaign lines are being written by the Tories themselves.

As the strikes continue, there is no doubt the party’s left is genuinely concerned about the plight of ordinary workers struggling to make ends meet during a cost-of-living crisis.

But while some non-aligned voters have sympathy for striking rail workers, others complain about the inconvenience of the industrial action to their own work, livelihoods and holiday plans. And the longer the strikes go on, the louder these complaints will get.

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From Sir Keir’s perspective, neither Labour nor the country can afford to lose the next election and allow a right-wing Conservative government to be in power for the next five or 10 years.

The Labour leadership is desperately trying to keep its eyes on the prize, which means, primarily, focusing on winning over Middle England, because, like it or not, that is where most of the seats are, and that will determine who gets into Downing Street.

The Labour left’s political purity will not get the Opposition into power as was clearly shown in 2019 when the party had its worst result since 1935.

After years of domination under Margaret Thatcher, Labour finally realised it had to change for there to be a change of government. A political realignment had to be made to get into power and the plan worked because New Labour won three consecutive elections.

Even though some people might like it to be otherwise, the choice of UK government at the next election will not be between a Corbynite Labour Party and a Thatcherite Conservative Party but between a modern progressive Labour Party and a Thatcherite Conservative Party.

As Tony Blair himself once said if you put a traditional Labour Party up against a traditional Tory Party, you get a traditional result. The last 50 years in Britain have shown us that he was right.

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