The thing about music, perhaps more than any other art form, is that not only is it unclear what it means at any given moment, it often loses its meaning the second the composer sets down his pen. Beethoven's Fifth Symphony – what is that? The clues we have are tenuous – most famously, one account has it that the composer described his famous four-note opening motif as "Fate knocking at the door." Most scholars agree that this witness was either making it up, or that Beethoven just said anything to avoid irritating questions. Not helpful. But if we can agree (can we?) that it is heroic, cleaving as it does to the straightforwardly macho C major key, what heroism did he mean?

You see the problem. Beethoven himself could be indecisive. His Eroica symphony, the Third, was composed as a hero-gram to Napoleon, then, after that particular dictator showed his true colours, Beethoven furiously scrubbed out the dedication in the score. As for the Fifth, well, both sides used it as a victory anthem during World War Two. What Beethoven intended, his truth, at that point ceased to matter.

That's how it is with the arts. In that I include the most slippery art form of all, news reporting. I realised with a jolt just how close the world of news reporting is to that of entertainment when, in the newsroom of a UK national newspaper, I once declined to write a big story on how "Andrew Lloyd Webber has lost it" on the basis that it wasn't true. "Come on, it's only news!" rejoined the news editor with a grin.

Entertainment is usually as much as anything about two things, from the point of view of its creators – audience numbers and drama. I increasingly believe that nearly everything is filtered at some point through those two factors. Add to that the natural bias of many news reporters for or against their subjects and you have something much closer to a work of theatrical art than to objective, detached reporting of the facts. Not to say that much of news reporting doesn't do a great service, but the point remains. Playschool also does society a great service.

The reporting of this Gaza war has resembled nothing so much as a host of freely creative interpretations of a work of art. Let me give you my view of the plot – three Israelis murdered against a background of constant political tension threatens explosion of violence in the region, of which a Jewish revenge attack is a symptom but whose culprits are quickly arrested by Israel; the Israeli government seek to defuse tension, send back-channel missives to Hamas to avoid war and maintain quiet, Hamas launches thousands of rockets and their vast attack tunnel network is soon revealed.

They fire from amidst civilian centres, next to schools and UN buildings even though most of Gaza is actually unpopulated, and although Israel seeks to avoid loss of civilian life there is inevitably some (though those numbers are exaggerated by Hamas). Responsibility therefore lies with Hamas, yet still Israel is wracked with sorrow.

That's not what most news reports have been showing. What we get there seems at times as twisted as Beethoven's Fifth Symphony being used by the Third Reich.

And no, I'm not calling Al Jazeera or CNN Nazis, of course not, but there is a time when truth gets manipulated and lost. And you know what? That's not actually what they call art. It's what they call propaganda. Someone should write a play about that.

James Inverne is an arts writer and broadcaster