🔗 Share this article Japan on course to choose woman prime minister in historic first Over the last two decades, Japan has seen more than 10 leaders. In fact, one expert likens taking up the country's top job to drinking from a "poisoned chalice". But why does Japan keep changing prime ministers? This is partly because of it being a "single-party system", says Professor James Brown of Temple University Japan. The Liberal Democratic Party's control on the political landscape means the primary rivalry comes from within the party, rather than from opposition groups. "So within the LDP there are intense conflicts within various groups - they all desire their own clique to get the leadership position." "Thus although you might be chosen as prime minister, as soon as you're in office, you have many individuals manoeuvring to try to get you out again." Key Factors Behind Frequent Changes Single-party rule restricts outside challenges Internal factional rivalries fuel leadership contests The prime minister's position is frequently called a "poisoned chalice" Political stability remains difficult to achieve despite economic strength