This was always going to be the most dangerous time for the Coalition.

They knew this. If there were no signs of the austerity package working, two years on, Messrs Cameron and Clegg understood that they would be in big trouble. Their expectation was that the shoots of growth would be starting to appear, and they were also pinning hope on the Queen's Jubilee and the Olympics to provide an added feel-good factor at this very time.

They could not have foreseen the eurozone crisis, which is deep and will get much worse. It could well wreck any lingering hopes of a genuine economic recovery. But something else is happening, and it could be much more significant, in the context of UK politics, than anything else. Labour is back.

The leadership of Ed Miliband has been anything but dynamic, but it is shrewd, and for the long-term. Most people I know find if hard to see him as a UK prime minister in waiting, yet there are plenty of plus points, and he is certainly emerging as someone who is very good at selecting and managing a team. Also, his speeches are reflective and intelligent; they resonate, often long after they have been erroneously dismissed. Take the concept of "the squeezed middle". It was not Mr Miliband's, but he took it up – and was duly derided for it. Now, a year or so on, it resonates, and how.

Mr Miliband is making some very good appointments. His shadow team includes various notably able women – Yvette Cooper, Caroline Flint, Rachel Reeves and Liz Kendall. And last week Mr Miliband made his most significant appointment yet. He placed Jon Cruddas in overall control of policy. Mr Cruddas is not a household name, certainly not in Scotland, for his roots are very much in south-east England. He is highly respected in the trade union movement, which Labour simply must keep on board, and he understands that social conservatism could be a vitally important part of the Labour message. He is an old-fashioned, independent-minded English patriot.

Mr Cruddas is just one of a very strong team that Mr Miliband is shaping. His shadow business spokesman, the eloquent and cerebral Chuka Umunna, is only 33 years old but is already the smoothest political performer around, and is surely a potential leader of the party. Liz Kendall, Shadow Minister for Care and Older People, was only elected in 2010 but has already made her mark. She knows the NHS inside out, and it is clever to have as Shadow Minister for the elderly a relatively young MP.

Meanwhile, north of the Border, Johann Lamont is enjoying a very impressive debut as Scottish Labour leader. Her greatest strength, up till now, was simply that she is not Iain Gray. That is not meant unkindly; it is just the reality. But she is building on that, and she can certainly rattle the hitherto imperious Alex Salmond.

Indeed a combination of a Labour revival in Scotland and parallel progress for Mr Miliband and his team south of the Border could yet entail serious trouble for the SNP and its flagship policy. If the referendum on independence, in just over two years, takes place against a background of a sustained Labour revival, south of the Border as well as north of it, then many Scottish Labour voters, who have temporarily "lent" their support to the SNP, might think seriously about returning home, in a political sense.

If Labour really looks capable of winning the 2015 UK General Election outright, that might be enough to persuade many merely lukewarm supporters of Scottish independence that it's maybe not such a bright idea, after all.

And then there's Tony Blair. Yes, he's back. That makes me cringe, yet I have to admit that in terms of sheer political verve and chutzpah, he could yet be Labour's best weapon. Altogether things are looking much better for Labour, in both the UK and the Scottish contexts, than they have for four or five years.