For relief from the monumental argument between the British and French governments over Iraq, there is, strangely enough, an exhibition in London at Tate Britain, on Millbank, which serves the purpose. It reflects an unusual period when British artists exhibited at the Paris Salon and French artists came to work in London, and when French rulers remembered with affection their periods of exile in England.
Never before or since has there been such a high level of cultural and political interchange between the two countries. For a brief 15 years it was much more intense than it was during the period of the Entente Cordiale, whose centenary will be celebrated shortly. The period was 1815 to 1830, and the exhibition is entitled "Constable to Delacroix".
Of course, the two sides continued to make remarks at the other's expense. As British visitors poured into Paris, Carlyle said that "to live in Paris for a fortnight is a treat; to live in it continually would be a martyrdom." Referring to British painting, a French critic remarked that the British, despite their prodigious materialism and genius for literary and scientific invention, were simply "varnished barbarians" when it came to the visual arts.
The reference to literary invention meant the novels of Sir Walter Scott, which were published in French as soon as they were available in Britain, and the poetry of Lord Byron, whose translator said their popularity arose from being "in harmony with the atmosphere of disorder and passion in which we live". And "varnished barbarians" or not, the paintings of Bonnington, Constable and Lawrence had an immense impact at the so-called British Salons at the Louvre of 1824 and 1827. "The only thing your talent lacks," Géricault told a painter friend in a letter from London, "is to be steeped in the English School... colour and effect are understood only here."
But perhaps the most astonishing aspect of this rare period of good will and mutual admiration is its starting date, 1815. This was the year of the battle of Waterloo, the final overthrow of Napoleon, the arrival of allied troops in Paris. Indeed this golden period of friendship, 1815 to 1830, developed in the immediate aftermath of the very last occasion on which the two nations went to war against each other. Now it is only around the horseshoe table of the UN Security Council in New York or at a European Council supper in Brussels that we quarrel. Again, however, "rapprochement" is likely to follow in short order.
Paradoxically, Tony Blair is more respected by the French here in Paris than he was before all this started. Although the French ruling class absolutely disagrees with the Prime Minister's policy, its members have understood his courage and know it for what it is. After all, they are politicians too.
They comprehend that he is a moralist and an internationalist, though not in the way they would choose to be. They see that Mr Blair's stature has increased even as his political strength has declined – though the Prime Minister's methods bring to their minds the advice given to his colleagues by Talleyrand, former bishop, foreign minister for Napoleon and chief minister in the first post-Napoleon government in 1815: "Surtout, Messieurs, pas de zèle!"
Moreover, France can make no progress with its plans for constructing a European military force without the full-hearted participation of the British. At the moment France is constrained to discuss these matters with pacifist Germany and tiny Belgium. Britain's armed forces exceed France's in size and capability, as President Chirac openly admits. And in a second paradox, the value of Britain's military assets for Europe as a whole is increasing by the minute as the war in Iraq unfolds. There is no substitute for experience.
Britain and France are looking at the same damaging split in Europe. While neither party likes what it sees, of the two, France is probably the more uncomfortable. For "old Europe", led by France and Germany, is economically the least successful part of the Continent. The best measure is unemployment. It is rising fast in France and Germany whereas the latest British figures showed record levels of people at work.
That is why, along with Spain and Italy, the East European nations knocking on Europe's door are more inclined to follow Anglo-Saxon policies than inflexible French and German practice. The problem for France is that following enlargement, Anglo-Saxon style countries will be in the majority. As it is, the combined gross domestic product of the UK, Spain and Italy exceeds France and Germany counted together.
But Britain also needs Europe. Frankly I have felt increasingly uncomfortable with Britain's role as the United States' only significant ally. It hasn't been a pleasant experience. The cogs and wheels of co-operation have been sprinkled with grit. The only "special" aspect of the relationship is its demeaning one-sidedness. In addition, the types of American right-wing politicians with whom we are forced to work would get no hearing here. I don't believe any future British prime minister, Labour, Conservative or Liberal Democrat, will again put the US before Europe. More than ever, it seems to me, Britain's destiny is with Europe. The quarrel over Iraq doesn't change that.