SIGNS of left-wing resurgence are everywhere: in the summer of strikes and the rediscovered power of trade unions; in the weekend’s French elections which saw a revivified left hobble centrist president Emmanuel Macron; in the success of American Apple workers who just voted for the first time to join a union; and in the election of Colombia’s first left-wing president.

Politically, there’s a sense of an incipient "redness" in the air. But what about Scotland, the ancestral seat of the British left? Well, here at home there’s a war going on over the soul of the Scottish left. The combatants are the Scottish TUC, the Greens and the Scottish Labour Party. Few would still define the SNP as "left" in any true sense – so the Government isn’t on the battlefield.

The conflict really came into focus last week over the totemic issue of free school meals. Scottish Labour accused the Greens of betraying children by voting against extending free meals beyond P5. Moves to claim left-wing ground by Scottish Labour, though, are clearly hampered by Keir Starmer’s Blairism.

Read more: Unions digging in for a battle with Sturgeon, the heir to Blair

Labour MSP Monica Lennon pointed to the Greens' own manifesto pledge on free school meals, calling it a “staggering u-turn”, and a “stomach punch to everyone who voted Green”. The Greens, Ms Lennon said, were a “pale imitation of the party they claim to be”.

Significantly, the STUC – an increasingly powerful voice of the Scottish left – wants free school meals for all state school pupils. In a stinging social media post, Labour MSP Katy Clark said that in just one week, the SNP and Greens voted down putting the right to food into law; free school meals for all state school pupils; and compensation for unfairly convicted ex-miners – the latter being a highly symbolic issue among the left.

Ms Clark added: “There’s nothing progressive about those votes.” The left-wing former Labour MSP Neil Findlay said: “What a Scotland we live in, we have a national food emergency and the Tories and Liberals supported a Labour amendment to the Good Food Nation Bill for free school meals for all. The SNP and Greens voted it down.”

Neither Nicola Sturgeon nor Patrick Harvie turned up for the school meals vote, and were dubbed "Meal Stealers". Both were accused of caring more about Indyref2.

STUC General Secretary Roz Foyer attacked “political leaders” for “flagrant duplicity, leaving children throughout the country in entirely avoidable poverty and hunger”. Ms Foyer added: “Child hunger is a political choice.”

The STUC and the Poverty Alliance charity last week held a Cost of Living Crisis Summit aimed at forcing the UK and Scottish governments to help the millions facing ruin today.

Yesterday I asked Ms Foyer what she made of the SNP and Greens. Here’s what she said: “The failure of the Scottish Government to adequately provide food for hungry children is a stain on our social fabric.” Any progress that has been made is “too narrow in scope, too slow in pace and far too late for those who go to bed every night defeated by hunger.

“Our movement will lead on this. We can no longer afford to wait on political leaders to do the right and progressive thing during a cost of living emergency. We can be in no doubt that we are now on an emergency footing, with food prices, inflation and rent rising whilst wages stagnate. We intend to bring forward a National Food Summit, one that convenes those who are committed to making child poverty and hunger a distant memory. We cannot do it alone and we must see the Scottish Government match our ambition to ensure every child throughout the country has access to food.”

I also asked the Greens about accusations that they’d lost their progressive edge and were now seen by many on the left as simply doing the SNP’s bidding. Green MSP Mark Ruskell said: “Labour is desperately trying to re-position itself as a ‘radical fringe’.” Labour, he claimed, moved “incompetent amendments and motions which parliament is then forced to vote down. They are also pretending Greens aren’t delivering policies when we actually are. You campaign in poetry and govern in prose … Ultimately radical movements are judged not by words but by what they actually deliver and I think we have made good first steps.”

Read more: STUC leader: 'The cost of living will crush us — and Scottish independence won't help'

Patrick Harvie told me: “Some of the attack lines from Labour … are pretty shallow. Their main tactic seems to be to pick out an element of what we’re already doing, come up with a flawed, unrealistic, uncosted or occasionally even unlawful version of it, and then try to claim some kind of moral high ground when we vote against it. Regardless of this kind of game-playing, we are cracking on with expanding free school meals, legislating for the right to food in a comprehensive human rights bill [and] building a national system of rent controls … Delivering on the commitments in the Bute House Agreement will represent huge progress on the Green agenda in Scotland – an agenda that’s not just about saying radical things, but about getting the detail right and making practical change happen.”

One Green MSP who asked to remain anonymous, however, told me they remain “sceptical about the Cooperation Agreement”. The SNP, they said, “is not a radical party – it is a national party”. They worry over the “level of compromise” required, but believe that the agreement means Greens can make the SNP “more radical”. The last nine months, they added “have not been without their frustrations”. However, they insisted that Greens hadn’t “lost our progressive edge”. Though they admitted: “I do understand why people … think we are doing the SNP’s bidding, but that is clearly not what is happening in the meetings I and other Greens MSPs have with [SNP ministers]”.

“Pluralistic politics is not something that comes easy to the British psyche – the two-party system is so deeply entrenched. That we are trying something different in Scotland is significant.”

For those on the left, though, and the wider Scottish electorate, the question is now being raised about who really represents the working class and progressives: Scottish Labour, the Greens, or a trade union movement which has found a new raison d’être?

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