Is it frivolous to be making or talking about theatre while people are dying in Gaza? That was one of the issues raised at last weekend'sDevoted and Disgruntled, particularly as Saturday's sessions coincided with the demonstration against Israel's actions in Gaza. As one theatre-maker observed: "I want to feel useful, not decorative."

As those of us who marched against the invasion of Iraq know all too well, demonstrating in a democracy often changes nothing. But can theatre do more? Can it engage quickly with such crises, and can it play a part – if not in fixing the world, then at least in helping to change it? Or are we just kidding ourselves? After all, the South African government wasn't exactly trembling during apartheid just because London audiences were on their feet cheering the cast of Poppie Nongena.

As one D&D participant pointed out, making a piece of theatre is time-consuming – and by the time you've made it, the urgency of the moment has often passed. In a subsequent conversation, Chris Goode recounted how when he was at Camden People's theatre, it was possible to quickly make and mount a piece about the coming war in Iraq that then played in the theatre the week the first bombs were dropped.

But that's the exception rather than the rule: take Called to Account, which didn't play at the Tricycle until 2007. Because of access to space and resources, and the fact that programming happens so far in advance, it is often difficult for theatre to achieve that kind of immediacy. The poets of the first world war could produce their poems instantly, but it took 10 years for a masterpiece such as Journey's End to emerge.

Does this mean that a show about Guantánamo Bay, staged several years after the camp was set up, is the theatrical equivalent of shutting the stable door after the horse has bolted? Or can it help to shake us out of our complacency? Are there some issues that are so sensitive that it feels too soon to tackle them, rather than too late?

Edinburgh in 2002 was full of American students emoting about the twin towers in a way that felt like drama was therapy, rather than incisive political comment. On the other hand, young US companies such as The Team (whose Architecting was at Edinburgh last year) seem engaged with trying to explore the psyche of their nation, much more so than their UK counterparts, who seem content to leave that kind of thing to David Hare.

If you do succeed in making a piece, what is the best form and function? Too much metaphor can be a cloak against the rawness and immediacy of what's going on. And although, at the very least, the piece might inform, often it's only preaching to the converted. I've seen some fantastic shows about the human cost of our asylum policies, but it is government ministers who should be seeing them, and they never show up.

Does that mean that theatre should just wring its hands and do nothing? Theatre quite patently can't fix Gaza, but perhaps it can help explain it. There's something honest, even mature, about acknowledging our powerlessness. It is a spur not to giving up, but to going on – even if it sometimes feels as if we are merely stumbling around in the dark.