What it is: (1) Recurring conflict between the Christian countries of the West and the Muslim countries of the Middle East and Asia, dating from the founding of Islam in the 7th century (2) The 20th century conflict between Communist countries in the East and capitalist countries in the West.

What it means: 'East is East, and West is West, and never the twain shall meet', begins Rudyard Kipling's ballad set in 19th century Afghanistan during one of Britain's attempts to get control of it. (In one sense they do meet, of course: the world is round.) Kipling was referring to the divide between the colonialist countries of Europe and the exploited countries of Asia, though in the poem even a man from the East can be a hero if he does it the British way. Antagonism between Christian and Muslim countries is also sometimes spoken of as an East-West division. This is a dangerous simplification. Both 'East' and 'West' hold a staggering variety of peoples, beliefs, languages and cultures in a staggering variety of landscapes and climates. Lumping them together is, at the very least, insulting. There is another use of the term 'East-West conflict': it can refer to the Cold War, when communist countries in the East and capitalist countries in the West came close to wiping each other out with nuclear weapons. The war's East-West frontier - the 'iron curtain' - ran from north to south across Europe, dividing Germany in two on its way. The capital of Communist East Germany was Berlin. At the end of the Second World War Berlin had been split into 4 sectors, one for each of the Allies. The Soviet Union kept one sector (East Berlin) and West Berlin was divided between America, Britain and France. At first all four had worked together, but the Soviets began to fear that they might lose their control of eastern Germany, with Berlin at its heart. In 1948 they closed all access into the 'land island' of West Berlin, to isolate it from western Europe. For almost a year the US and UK air forces broke this blockade with the Berlin Airlift, bringing in food and other supplies daily (a total of over 270,000 flights). In 1949 Germany was politically divided into two separate republics. During the 1950s West Germany prospered, but East Germany did not, and people began to cross from the East into Berlin's western sectors. To stop them, in 1961 the East German government built a high wall enclosing West Berlin, dotted with watchtowers, minefields and booby-trapped fences. Over 100 people were killed in attempts to cross. In 1989, when Communist governments were failing, Berliners rebelled and began to pull down the Wall that had separated families and friends for nearly 30 years. Berlin had been a symbol of the East-West conflict, and the dismantling of the Wall now became a symbol of new hope for peace. Germany was re-unified in 1990.

Think about it: The East-West conflict that has lasted longest is the clash between Western countries with Christian histories and Eastern countries in which the dominant religion is Islam. Some Muslim fundamentalists have declared their ambition to create Islamic states wherever possible, and some are prepared to fight to do it - just as Western countries have tried to impose their styles of government and life on the East. The clash is also represented in hostility between Arab people and non-Arabs, and the conflict in Israel provides examples of that. Think about the views of an Arab thinker, Edward Said, who worked throughout his life (he died in 2003) towards peace between East and West. 'The terrible conflicts that herd people under falsely-unifying terms such as "America", "the West, or "Islam"', and invent collective identities for large numbers of individuals who are actually quite diverse, must be opposed. Rather than the manufactured clash of civilisations, we need to concentrate on the slow working together of cultures that overlap, borrow from each other, and live together. For that we need time, patience and faith.... I have spent a great deal of my life advocating the right of the Palestinian people to national self-determination, but I have always tried to do that with full attention to the reality of the Jewish people and what they suffered by way of persecution and genocide. The paramount thing is that the struggle for equality in Palestine/Israel should be directed toward humane coexistence, not further suppression and denial.'