As Europe struggles with its worst migration crisis in more than half-a-century, all eyes are once again on Angela Merkel. The German chancellor took a huge political gamble this week by tearing up the EU's rulebook, while also demanding a new deal that would force Britain to accept hundreds of thousands of refugees.
Faced with a human flood, Mrs Merkel has abandoned the Dublin Convention that requires asylum seekers to be processed in their country of arrival.
Berlin's new policy will allow Syrian refugees to apply for asylum in Germany, rather than in their first port of call.
Deciding to do such a thing without the approval of Brussels will surely encourage other EU countries to pursue their own migration policies too. But this is the last thing Mrs Merkel wants.
She and President Hollande of France have just called for a new, binding European agreement to share the asylum burden.
Her proposals, however, were greeted with incredulity by other member states, their inherent flaw being that they would give millions more migrants an added incentive to come to Europe.
David Cameron, along with other leaders, is resisting Mrs Merkel's move, despite moral blackmail from EU and UN officials.
Mrs Merkel may not like it, but many Germans, in a country which is expecting a record 800,000 asylum seekers this year, feel that they have already taken more than their fair share. They blame their coalition government for being a soft touch and street protests are reaching a crescendo.
Mrs Merkel was greeted by angry protests and shouts of "traitor" this wek as she visited an embattled refugee hostel near Dresden. Solving this crisis is proving to be the greatest challenge of her career.
The consensus in Berlin is that Europe's combination of open borders and different national immigration policies is unsustainable. The present uncontrolled influx is not how the system is designed to work - but the scale of the exodus from the Muslim world means that rules are being flouted as each country protects its own interests.
Meanwhile, the lack of border controls within Europe is allowing migrants to make for countries with generous rules on asylum and welfare, especially Germany and the UK. Britain, with a strong economy, is a powerful draw for migrants but is outside the borderless Schengen area and home secretary Theresa May is determined to keep them out.
Unsurprisingly, the German media is portraying the Tory government as selfish. The blame game is, however, as pointless as it is undemocratic. Britain will not accept an EU policy that imposes quotas of migrants without consent. Nor will most other countries - including Germany.
So the EU's asylum system is buckling and everywhere support is surging for extremist parties of Left and Right.
Mrs Merkel, European figurehead, has the experience and authority to restore order to the anarchy. And Mr Cameron has hitherto enjoyed one of the best relationships with the chancellor amongst European leaders. He has, moreover, a direct interest in reforming the EU's migration regime as it is bound to loom large in the coming referendum.
The first priority for the EU must be to stabilise the crisis that began with the fallout from the Syrian civil war.
That would require the EU to impose much stricter external border controls, while helping Mediterranean countries, the first ports of call, to accommodate asylum seekers and process their applications. Mrs Merkel has promised to do more to help Greece and Italy cope and today she will attend a summit in Vienna, where Balkan countries will also demand aid, especially Macedonia, which has declared a state of emergency.
The next step would be to restore a measure of national sovereignty to the larger question of economic migration. Mrs Merkel refuses to compromise on the principle of free movement, but she could show more flexibility by allowing each country to interpret that principle in its own way. Right now, she faces a stark choice between nation states acting independently or the creation of Fortress Europe.
Either the EU permits the restoration of national control over immigration - which means the end of free movement within Europe - or the EU turns itself into a fortress, excluding genuine refugees as well as economic migrants, while preserving its internal freedom of movement.
Meanwhile, having unilaterally abrogated the Dublin Convention, Mrs Merkel can hardly expect other countries to accept an EU diktat, especially if it obliges them to absorb migrants in very large numbers. So perhaps Europe would indeed do better to adopt a more empirical, every-man-for-himself solution, giving states free rein to decide for themselves how to deal with migration. It is pretty much what Germany is doing now.
Daniel Johnson is editor of Standpoint magazine