To the outside world, it may be hard to understand how a provincial election can shake the political establishment in Berlin and endanger the authority of Angela Merkel, German chancellor and Europes most powerful politician. It is also hard to conceive how a disastrous earthquake and tsunami in Japan can cause a political upheaval in the heart of Europe. Yet those two things happened at the weekend when Ms Merkels mighty Christian Democratic Union suffered a humiliating defeat in the southern state of Baden-Wrttemberg. The result victory for the centre-left and environmentalists could see a sorely weakened coalition in Berlin limping to the end of its term in office in 2013, with both CDU and the Free Democrats, its liberal junior partner, riven by internal divisions. They may be unable to push legislation past a substantial hostile majority in the Bundesrat, the upper house of parliament where the 16 federal states are represented. If they lose one more state election in September, Ms Merkel could face a blocking majority of Social Democrat, Green and far-left Linke votes in that chamber. In terms of foreign policy, in Europe and on the wider world stage, the election defeat could compound the indecision that has marked German policy in recent months on issues such as the eurozone crisis and the Nato military intervention in Libya. A string of seven state elections in Germany this year of which Baden-Wrttemberg was always seen by the government as the most critical saw Ms Merkel take an increasingly strict position in eurozone negotiations. Fear of a backlash within her own party, and from the FDP, persuaded her to set a firm cap on any German financial guarantees for debt-laden member states, and to block the introduction of euro-denominated bonds to help them. Now she has lost the election, however, there seems little prospect of relaxation. Her status within her own party is weaker as is that of Guido Westerwelle, the FDP leader and vice-chancellor. The same caution holds true in foreign policy. When in doubt as she was when Germany abstained in the UN Security Council vote to impose a no-fly zone on Libya the chancellors instinct is to play safe and not alarm her electorate. The decision not only infuriated Germanys Nato allies, it alarmed many of her own conservative supporters, who saw a return to German isolationism. It also failed to help her on Sunday when, after almost 58 unbroken years in power, the CDU was voted out of office in Germanys most prosperous state in favour of what will be a Green-SPD coalition. The FDP was reduced to barely 5 per cent support the minimum to enter parliament; in elections next door in Rhineland-Palatinate, it was wiped out. Sunday saw a surge in support for the anti-nuclear Greens, on a wave of public horror at the prospect of a nuclear catastrophe caused by the Japanese earthquake. Every other party in the German political firmament saw a drop in support. For the Greens, the days one big winner, it was a historic turning point, in the words of Claudia Roth, joint national chair. The former party of protest will have a Green premier to run the government in Germanys most economically successful and conservative state. The SPD, the alternative great peoples party to the CDU ever since the second world war, will have to play second fiddle to the environmentalist upstarts in the state parliament in Stuttgart. It has also dealt a grievous blow to Ms Merkels party and to her own position, as well as to the smaller FDP and its leader, Guido Westerwelle. For both parties, Baden-Wrttemberg represented not merely an apparently impregnable conservative fortress but a core part of their origin and identity. It has caused media commentators to speculate whether it marks the twilight of the chancellor now in her second term of office. Most political scientists maintain, however, that such speculation is premature. Karl-Rudolf Korte of Duisburg-Essen university sees the result as damaging for the chancellor but not disastrous. For Ms Merkel as chancellor, it is not a problem, he says. Her majority in the Bundestag [lower house] will survive. No one in the coalition wants an early election. More difficult is her position in the party. The core of CDU identity is affected in Baden-Wurttemberg, says Prof Korte. There is conservative dissatisfaction. But I do not see an organised resistance. There is no charismatic antagonist. Jurgen Falter, professor of politics at Mainz, sees the greatest problem inside the Berlin coalition, where the Free Democrats have been greatly weakened. It is a catastrophic result for the FDP. Baden-Wrttemberg was a party citadel. So Angela Merkel and the FDP will try to save themselves till 2013, just waiting for something to turn up. When Ms Merkel and Mr Westerwelle, her vice-chancellor and foreign minister, spoke to the press, the shock to the system was clear. Both sought, however, to blame the consequences of the Japanese quake as the primary cause of their electoral defeats. It is a very painful defeat, a solemn Ms Merkel said. But the theme of nuclear safety had dominated the final days of the campaign. For me, Japan was a unique event, she said. Japan means we cannot simply stick to business as usual. Mr Westerwelle, whose own leadership had already been under question for months as the FDPs poll ratings slumped, admitted that the quake alone could not explain its poor performance. There is nothing to gloss over, he said. We got a black eye. Nuclear energy played a special role in these elections. But we must be self-critical. If we liberals had been in better form, this catastrophe in Japan would not have affected us so badly. Financial Times