BERLIN — She is considered the indispensable European, yet one of the biggest questions looming over the Continent’s crucial elections this year is whether Germany still regards Angela Merkel as indispensable, too.

Seven months before national elections in Germany, the prevailing wisdom has held that Ms. Merkel, now seeking a fourth four-year term as chancellor, is most vulnerable to the rising popularity of the country’s far right, just as other populist, far-right parties are gaining in coming elections in the Netherlands and France.

Yet suddenly, Germany’s left has unexpectedly resurged, prompting Der Spiegel magazine this weekend to pose a question on its cover: “Will She Fall?”

A reliable answer is not in sight. The shocks of 2016 — Britain’s vote to leave the European Union and the election of Donald J. Trump as president of the United States — have profoundly shaken Germany, which depends more than any other European nation on Pax Americana and global institutions set up after World War II.