When I was younger, you used to hear a lot about the generation gap: young people and their parents were said to inhabit different cultural worlds, epitomised by a range of issues but most particularly by their taste in music.

Yesterday’s rally in Melbourne in defence of live music is as good an occasion as any to proclaim the death of the generation gap. The crowd ranged from teenagers through to the oldest of the boomers, now in their 60s; they may not listen to the same bands, but they share the same musical sensibility and a determination to defend it. Rock has won this battle.

It was only when the protesters reached parliament house that they saw the representatives of a different culture. Coalition MPs did their best, brandishing signs is support of live music, but they were greeted with shouts of “F-ck off Liberals”. Although MC Brian Nankervis tried to make them welcome, saying “we’re all in this together”, many looked decidedly uncomfortable in their new role as defenders of popular culture.

Of course, it isn’t just the coalition that has a problem; indifference or hostility to rock music can be found on both sides, which is how the issue got out of control in the first place. Many MPs are themselves steeped in Melbourne’s music culture, but others instead listen to the bureaucrats who hate its disorderliness, to branch members from the pre-rock era, or to foreign ideologies that see rock as the voice of the devil.

Despite the fact that this cultural divide runs down the middle of the Liberal Party, opposition leader Ted Baillieu has embraced the cause of live music as a convenient stick with which to beat the Labor government. This sort of adaptability comes easily to a party that has been in Opposition for a decade; desperation tends to take over, and MPs are willing to try almost anything that might get them back into government.

The one party that should be most attuned to rock sensibility is the Greens, who were strongly represented among the protesters. But they have seemed to lag behind on the live music issue, taking their time to formulate a position and then struggling to get a simple message out.

This may be partly due to a lingering strain of puritanism in the party, but it also stems from the Greens’ obsession with process and consensus.

They are strong on long-running issues of principle, but not so good at adaptability; when a new issue comes up, it takes time and effort to work out a line and then get everyone behind it. The Liberal Party, naturally authoritarian and somewhat given to opportunism, has no such difficulties.

The Greens may also figure that it doesn’t really matter, that in the end they will benefit from the issue regardless of what they do. Angry music fans want to punish Labor, and in the inner-city the Greens are the only alternative. They and the Liberals are travelling different routes, but look like ending up in the same boat.