In his column, Drummond compares UKIP to the Nazis and says that the posters offend him morally and aesthetically. He goes on to suggest that he might do every other UKIP poster he can find. Hoping to get some public support her says that he's worried that the police might come for him but it's all in the name of art dahling. Instead he's been told what an idiot he is in the comments and convinced some people who were unsure to vote for UKIP!
Despite what he says, Drummond hasn't destroyed the poster in the name of his art he's making a political statement. He's committed hundreds of pounds worth of criminal damage and bragged about it in his newspaper column. It wasn't clever, it wasn't "ironic", it was just stupid and hopefully the police make an example of this pathetic self-publicist.