Paul Durand-Ruel launched his career as a dealer in the mid-1850s, when he was in his mid-twenties. In 1857, he opened a gallery on the fashionable Rue de la Paix, moving to larger premises on the Rue Lafitte in 1869, on the eve of the disastrous Franco-Prussian War. During the war, he took refuge in London, where he staged a number of exhibitions. He also met Claude Monet and Camille Pissarro, two founders of the Impressionist movement, who had also taken shelter in Britain. The war itself was followed by the Commune, which ruled Paris from March 18 to May 28, 1871, and was bloodily suppressed. In June 1871, Durand-Ruel paid a brief visit to Paris. By the end of September he was once again based there. Later, he expanded internationally, basing himself on his experiences in London.

It is worth spelling out this sequence of events because one of the things that emerges strongly from the exhibition at the NG is how determinedly apolitical the Impressionist movement was. So much so that it looks like a deliberate choice. The first half of the 19^th century in France is replete with major political paintings, from Jacques-Louis David's Napoleon Crossing the Alps (1801-5) to Gustave Courbet's The Studio (1854-55). Subtitled “A Real Allegory," this painting confronts an image of the painter himself as protagonist with the figure of a hunter who resembles Napoleon III. Peripheral figures spell out the artist's criticisms of the corrupt society of the Second Empire. To all this, Impressionism deliberately turned its back. Durand-Ruel was a political conservative—a Catholic who attended mass every day. He wished for the restoration of the French monarchy. Pissarro was Jewish, and sympathetic to anarchism. Monet, largely apolitical, was a supporter of Alfred Dreyfus, a Jewish captain unjustly convicted on charges of treason. Durand-Ruel was anti-Dreyfusard. Yet they all came together under the Impressionist banner.

This is not to say that the Impressionist painters were insensitive to the social nuances of their time. Monet painted views of the Seine with factories in the distance. No attempt there to deny increasing industrialization. But what the Impressionists were most concerned with was creating a new way of looking. Their paintings are politically and morally neutral. They had no apparent wish to change the world, only to represent it in what seemed to them a more accurate, more contemporary way. Their political statement, after seventy-or-so years of it, was to renounce political rhetoric in art and go back to the thing seen. Maybe the shock of the Franco-Prussian War had something to do with this.

In a real sense today's avant-gardism seems to be trying to turn the clock back, rather than forward. A great deal of the art now placed by critics, and indeed by the artists themselves, in this supposedly flattering category is an exercise in preaching to the converted. When Mark Wallinger won the Turner Prize in 2007 with a reconstruction, within the grandiosely official galleries of Tate Britain, of Brian Haw's “Peace Camp"—originally located in Parliament Square and protesting against West's foreign policies from 2001—the Tate's website stated: “Wallinger's work is noted for its succinct social commentary and political resonance." Resonance, my foot! In fact, the reconstruction clearly had less chance of making any converts to radical thinking than the ramshackle original, defiantly exposed in the open air for all the world to see.

Durand-Ruel, after considerable struggle (he nearly went bankrupt twice) made a success of his aim to establish the new and, to his contemporaries, visually challenging work of the Impressionists. If we take them for granted now, it is in part because of his faith in them. Not only his faith in the art itself, but also his faith in the commercial possibilities their work offered, within a rapidly evolving bourgeois society. New horizons were opening up. His biggest success was not in France, not in Britain, but in the United States: Impressionism eventually took wings from the expanding American economy. The magnificent loans from American museums in the NG exhibition amply demonstrate that. The whole idea of an “official avant-garde," which is what we now seem to have, is an oxymoron. It's an attempt to drag art back to the times when the official Salons still seemed to hold the key to building profitable reputations. It is easier of course to define the problem than to offer a solution to the current creative deadlock. But political rants smugly housed in museums aren't going to do it. Meanwhile go to the NG and enjoy a show that feels no impulse to shout at you.