This piece was supposed to be about the upcoming reunion of Oasis. On Wednesday, a note on Facebook alerted the world to an upcoming announcement from the popular troupe of Mancunian anorak wearers. Those aware the band had split up predicted they were set to emerge from the shadows and unleash another avalanche of shouty after-hours anthems. In the event, we were promised nothing more than a lavish reissue of the group's once unavoidable debut album Definitely Maybe . It seems the recording will emerge on such ancient formats as CD, LP and – unless I'm making this up – wax phonograph cylinder. A collective sigh passed through the world's social media.

Why would anyone care? It’s not as if the band broke any new ground. Oasis were, more than anything else, a skilled band of creative recyclers. A bit of T Rex, a touch of the Kinks and a large portion of the Beatles were crushed together to deliver the sort of tune that could, even after a vat of Bacardi Breezer, be sung at window-rattling volume.

It’s all about nostalgia. The mid-1990s were, for those of us in the western world, something of a golden period. We didn’t know it at the time, of course. That’s the thing about divine eras. It’s not until the good times have passed that we realise quite how fortunate we were.

That last thought needs a little unpacking. It is certainly true that, in Ireland at least, drunken carousers and technology millionaires were aware that something merry was afoot.

Suiting the mood
Whether you liked the notion or not, Oasis provided the soundtrack to the bacchanalia. You didn't need to own the records. You didn't even need to know who they were. Stroll through Temple Bar after nine o'clock and you would hear Don't Look Back in Anger being bellowed from a legion of bars that – despite actually being Irish – felt the need to assert their Irishness through the media of copper kettles and rusted road signs.

That tune became the Horst-Wessel- Lied of the New Hedonists. Unlike the Third Reich (excuse the excessive and tasteless hyperbole), this regime of unimaginable prosperity and boundless optimism surely would last for a thousand years. The nursery-rhyme lyrics – "Stand up beside the fireplace/ Take that look from off your face" – didn't make any explicit promises, but the tone of explosive defiance suited the mood very nicely.

Few other western nations were quite so transported. But the 1990s, alone among the post-war decades, balanced prosperity with political confidence. In 1989, following the fall of the Soviet Union, whole nations – hitherto shut away in grey isolation – blinked themselves back into the sunlight.

Unreality check
Anybody over the age of 40 will still feel a slight surge of unreality when they take a plane to Prague, Budapest or Tallinn. Before the fall of the Berlin Wall, those places seemed as remote and inaccessible as the outer reaches of Narnia. Terrible, terrible things happened in the former Yugoslavia, but we allowed ourselves to believe that the trend was towards freedom and stability.

The presidency of Bill Clinton now seems like a sort of cavalier extravaganza. Such was the growing economic confidence that his opponents were reduced to dragging up soiled dresses in their efforts to impeach. In contrast, every day of Barack Obama's premiership has been characterised by a ploughing through of resistant legislative sludge. For all his abundant flaws, Clinton was one of the few US presidents to end his period of office on something like a high.

We celebrate (or at least acknowledge) the 20th anniversary of two cultural phenomena this year. 1994 saw the release of Definitely Maybe and the broadcast of the first episode of Friends . Whereas sitcoms had, to this point, dealt with the affairs of the troubled and the excluded – the harassed medics of M*A*S*H , the working-class heroes of Roseanne – the signature show of the 1990s was defiantly aspirational.

You may be working in a coffee shop, but you can, apparently, still dream of sharing a vast apartment in gentrified Greenwich Village. There was a great deal of chatter about pre-millennial angst. But the cultural atmosphere was characterised by optimism and complacency.

The problem was not that we didn’t recognise the golden nature of the golden era. The problem was that – a few economic realists aside – we didn’t recognise that it was an era. The attacks of 9/11 soured the atmosphere. The subsequent economic collapse confirmed the depressingly cyclical nature of world affairs.

Oh well. There is some good news here. Good times always some to an end. But bad times also have their natural life spans. If Oasis lyrics made any sense, we would probably be able to close with a relevant quote from Noel Gallagher. Sadly, they don't.