One wonders what was going through the formidable mind of Angela Merkel as she brought in the new year. Just 12 months ago, the German Chancellor’s position seemed more secure than ever as she carefully shepherded Europe through two of its biggest crises in a generation, the near collapse of the Euro and Russia’s annexation of Crimea.

Yet, just months later she is starting to look uncharacteristically vulnerable. What a fickle business politics is. Ironically, after being attacked by critics throughout her career for a perceived lack of ideals and ideas, for refusing to look at the big picture, it is a bold, principled and emphatic policy decision that could bring Merkel down: her opening of Germany’s borders.

This mass movement of people from the Middle East and North Africa - most notably Syria - to Europe is arguably a bigger crisis than the other two put together, and will likely have a much deeper impact on the continent’s future. Again Merkel showed leadership.

As the crisis unfolded in the summer of 2015 many European states - including the UK – stalled, prevaricated and resisted. Merkel, meanwhile, was unequivocal. It was her country’s moral duty to help, she insisted, as makeshift reception centres filled up and hundreds of thousands made their way to Germany. “Wir schaffen das”, she repeated. We will cope.

Was her country’s recent, divided past and its terrible actions in the 1930s and 40s on the East German’s mind as she showed such extraordinary humanity? Very probably. But I believe she was thinking of the long-term future too – Europe’s economic decline and the ascendency of the east, the need to keep Germany’s population - and productivity - up.

Regardless of the reasoning, by the end of the year Germany had accepted more than a million destitute, desperate people; in comparison, the UK has agreed to take 20,000 Syrian refugees over five years.

From the outset, many ordinary Germans approached the influx with a calm, pragmatic attitude. The welcome was generally warm. But the sheer numbers involved, alongside concerns about integration and the strain on public services, exacerbated by the terrorist attacks in Paris, have gradually, predictably, changed the tone of the debate. Goodwill is running out and most Germans now want an end to the open-door policy.

Merkel remains steadfast, insisting numbers will reduce, but resisting a cap.

Meanwhile, her personal ratings plummet by the day, with much of the criticism coming from her own political allies.

This country of consensus and coalition is rapidly dividing and fragmenting, with the resulting mini vacuums being filled by more extreme right-wing, anti-immigration parties, such as the Alternative for Germany (AfD), a sort of Teutonic Ukip, which has seen its popularity and funding increase exponentially.

Five of Germany’s 16 states have elections this year in the build-up to 2017’s federal vote, and more support for the AfD could lead to increasing influence on future coalitions, perhaps changing the shape of German politics for the foreseeable future.

In the current climate, meanwhile, a homegrown Islamist terrorist attack would undoubtedly bring Merkel down.

With this in mind, it will be fascinating to see whether this consummate politician survives such an uncharacteristic outbreak of idealism – personally, I hope she does.