THE UR'S GUNGA DIN:

As she never tires of repeating, her strategy has three prongs: support for Ukraine, diplomacy with Russia and sanctions to bring Putin to the negotiating table. To see Germany leading the way in economic sanctions against Russia is extraordinary. In the early 1990s, I wrote a history of West Germany's Ostpolitik, culminating in German unification, and the first commandment of that Ostpolitik was that eastern trade should always go on. Sanctions were called for by the US and resisted by Germany. Today, Germany has more trade with Russia than any other European power. Its energy, machine-tool and other eastward-oriented businesses form a powerful lobby, not least within Merkel's own Christian Democratic Union. Yet she has taken them down the path of sanctions.

Of course Putin and the Russian separatists in eastern Ukraine helped, especially with the shooting down of a Malaysian airliner in July. But, unlike in the eurozone crisis, she has led rather than followed German public opinion. She has faced down the so-called Putinversteher - those who show such "understanding" for Putin's actions that they come close to excusing them. She has made the larger arguments, from history, about Europe, and they have resonated. I was particularly impressed by an interview I read with the boss of a German machine-tool company whose exports to Russia have been roughly halved following the imposition of sanctions. Yet this German industrialist said he fully supported them: "If [Neville] Chamberlain had imposed some sort of sanctions on Hitler, things would have been different. Both Hitler and Putin held their Olympics, and after his Olympics, Hitler went to war."

What is more, she has made the case for sanctions powerfully to more reluctant members of the EU, notably Italy, but also smaller east European countries where Russia wields much influence. To be sure, the formal chair of last week's European Council was the former Polish prime minister, Donald Tusk. It is a notable day in European history when a Pole speaks to Russia not just in Europe's name but with the whole economic and political weight of a European Union behind him. But Tusk is Merkel's trusted ally. Everyone knows she is Europe's real chair. In her Sydney speech, she again emphasised the vital importance of European states "speaking with one voice".

And then she has been lucky - an essential attribute for any successful stateswoman or statesman. (I can't bring myself to write statesperson.) Without a spectacular fall in the price of oil, the sanctions, which are still patchy, and not supported by China and other important economic partners of Russia, would not have had this dramatic impact.

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