Jeremy Corbyn has been making waves in Scotland, as he has been across the entire UK. His five-day visit has raked in the coverage and crowds, and annoyed his political opponents.

It wasn’t always so. Pre-election Corbyn wrote off Scotland as hostile and unfriendly territory. Now, against everyone’s expectations, he is back in play – after six Labour gains in June from the SNP, along with a small rise in their vote.

On his trip Corbyn visited 18 constituencies – 13 SNP and five Labour gains – drawing criticism from the Scottish Nationalists that he was avoiding Tory seats.

This ignored the fact that of the 64 seats Labour needs to win for a bare majority, 18 are in Scotland and all those are SNP held. The magical 64th – East Kilbride, Strathaven and Lesmahagow has a 3,866 SNP majority. It is not until Labour’s 96th target seat that you reach a Tory one – Renfrewshire East (formerly Jim Murphy’s seat) currently held by the Tories with a 7,150 lead over third-place Labour.

Corbyn held a “Festival of Socialism” rally at Glasgow University Union on Saturday which in its style – poetry, live music and speeches – drew inspiration from the independence movement. It was a sell-out event, packed with hundreds of enthusiastic young people who three years ago were avidly pro-independence.

He gets a good response at such rallies and his appeal is easy to understand. Corbyn talks as no other senior Labour politician ever has. He tells them that the neo-liberal consensus is a con and trickle-down economics a fraud. Ed Miliband might have had a similar political agenda, but he had the language of a policy wonk. Corbyn cuts through with his simple homilies in a way most politicians – the SNP included, Nicola Sturgeon apart – consistently fail to.

He tells the audience stories of the Labour movement, solidarity and internationalism. He quotes Keir Hardie and Chilean musician Victor Jara.

He comes over as authentic and consistent. But there is no sign of any strategy in Scotland to build on the success of June

But he was short on detail and the big issues of the day. There was nothing on Trident, Scottish independence or the SNP. There is also not a single word on the biggest challenge facing the country: Brexit. This despite a heckle towards the end of his speech to “say something” about it and the fact that, on the same evening, shadow Brexit secretary Keir Stammer had just made a major announcement on Labour’s policy.

Corbyn’s speech was rapturously received, yet it illustrated his cons as well as his pros. He comes over as authentic and consistent. But there is no sign of any strategy in Scotland to build on the success of June or any idea of how to take on the still entrenched, though weakened, Nationalists.

Corbynistas north of the border, organised around the Campaign for Socialism and the likes of Lothian MSP Neil Findlay, blame this on centrist Labour leader Kezia Dugdale, who they claim has little political hitting power. But while they dream of staging a coup, or Dugdale falling on her sword, their cupboard, beyond anti-Toryism, is equally bare.

Scotland has dramatically changed these past few months – with big implications for UK politics. The once omnipotent SNP has stalled and seems bereft of ideas. Ruth Davidson is that rare Conservative: popular and populist, having brought the Scottish Tories in from the cold. And Labour, for so long written off here, now has a semblance of life and energy – while still being a shadow of their former selves.

Corbyn and company don’t quite know what to do in such changed circumstances beyond what has worked before: campaigning, holding rallies and playing the old tunes. But they have earned the right to be listened to again, and that is a huge leap from where we were. Watch this space: what happens in Scotland could determine whether Corbyn eventually becomes prime minister or not.

• Gerry Hassan is author of Scotland the Bold and co-editor of A Nation Changed? The SNP and Scotland Ten Years On