Anyone who wonders about the role art can play in forming politics should go to the Hugh Lane. For my money, most political art doesn’t work well. The problem seems to be that political art has to make a point – or it isn’t political. But making a point runs counter to what we seem to seek from contemporary art – space to think, using the material given us by the artist as our starting point.

The involvement of the Laverys – John the painter and the subject of the exhibition at the Hugh Lane, and his wife Hazel, an American and also a very talented painter – is extraordinary. While Ireland was in turmoil from 1916 to 1922 and beyond, the Laverys were busy bringing both sides together. It was a heady mix of aristocracy, ascendancy, rebel, unionist and British government.

I have no idea if the dinner parties or acts of liaison helped or not – all was not rosy despite the socialising. But maybe the important contribution was via John Lavery and his paintbrushes. He seems to have been obsessed with doing portraits of the leaders on both sides, from the king to Edward Carson to Roger Casement to Michael Collins (who was perhaps also Hazel’s lover). Did sitting for John Lavery create a space into which other values could flow, ones which were not overtly political, ones which pointed to the human value of culture as apolitical proof of the value of humanity? Maybe. And maybe in this instance art – through portrait-painting – made politics work.

On a related point, to me the best work in the show is by social butterfly Hazel – a portrait of a girl. So it looks a bit as though she got to be lionised as a society beauty, and John got to be the heavyweight. For art, but perhaps not for the history of Ireland, that may be a pity.

Sir John Lavery: Passion and Politics runs at the Hugh Lane, Dublin, until 31 October.