18 driver. All these are now gone, or very much diminished. While there are intellectually convincing new rationales for the project, including the rise of non-Western giants such as China, rationales are no match for emotional motivators. The key to so much of this, especially on the economic side, is Germany. For much of its history, what has become the European Union pursued political ends by economic means. For Kohl and Mitterrand, the euro was mainly a political project, not an economic one. Now the boot is on the other foot. To save a poorly designed and overextended monetary union, the political must ride to the rescue of the economic. That will require Angela Merkel's leadership. If we are talking about the European economy and currency, Germany is the indispensable power. Only the combination of Germany and the European Central Bank, working in unison, has a chance of calming the mighty markets. For more than a year now, Merkel has attempted to find the narrow — perhaps nonexistent — line where the minimum that can be done to save the embattled Eurozone periphery meets the maximum she thinks German public opinion will bear. She has then tried to win her Eurozone partners to that course. So far, it has not worked. Now she needs to start from the other end: Work out, with the central bank and other Eurozone governments, what is the best, most credible deal available, and then put all her authority on the line to convince a reluctant German public that this is in the long-term, enlightened national self-interest of Germany. And it is. For no one has more to lose from the disintegration of the Eurozone than the Continent's central economic power. It may soon be too late. Timothy Garton Ash, a contributing editor to Opinion, is a senior fellow at the Hoover Institution and professor of European studies at Oxford University. HOUSE_OVERSIGHT_018102