The veteran chancellor announced Sunday she would run again in next year's polls and seek to govern Europe's top economy for a total of 16 years, which would equal the marathon term of her conservative mentor, Helmut Kohl.
"Many people would not be very understanding if now I failed to use all of my experience to do my duty for Germany," she told party faithful from her conservative CDU.
But she humbly rejected as "grotesque and absurd" the many accolades showered on her as the new "leader of the free world" who would keep the flame of liberal democracy burning in the era of Donald Trump, Brexit and rising populism.
While outgoing US President Barack Obama and The New York Times have cheered Merkel, many voters have become fatigued with the reign of "Mutti" (Mummy) and her right-left 'grand coalition' which utterly dominates the political scene.
Her renewed candidacy is a red flag to the ascendant populist and anti-immigration Alternative for Germany (AfD) party, which rails against a "political elite" divorced from the needs of the people.
"Under Merkel, democracy in Germany has withered and mutated into an all-party coalition," charged Alexander Gauland, deputy leader of the protest party which is now polling at 12 percent.
Criticism also came from other commentators who groaned at the thought of more-of-the-same after Merkel pledged to "work for more cooperation in this country", bolster the pension system and push on with the digital revolution.
"Did anyone understand why Angela Merkel wants to run again and what she wants to do in the next four years in office? I didn't," wrote Der Spiegel's commentator Dirk Kurbjuweit.
Based on what she said Sunday, he wrote, "we can expect Merkel to simply plod on, and that can't be the solution. The woman of whom so much is expected in these Donaldist times disappointed."
If Merkel was long considered invincible at the ballot box, she took a beating over her unusually bold decision to throw open the borders to a mass influx of refugees in 2015.
The fiercest critic in her own ranks, the head of Bavarian sister party CSU, Horst Seehofer, reacted coolly to Merkel's renewed candidacy, saying only that it was "good that we now have clarity".
The party's Markus Soeder was even blunter: "We should note Merkel's announcement with respect, if not exactly with euphoria."
To be sure, Merkel looks back at a strong record after 11 years in office, in which she battled to save the eurozone and sparred with Russia's President Vladimir Putin over the Ukraine conflict.
The German economy is humming, the budget is balanced, unemployment is down, and her country is widely seen as the strongest voice in a troubled EU.
Despite the bruising refugee crisis, 55 percent of Germans still say they would favour another Merkel term, according to an Emnid poll published Sunday.
"Merkel will do it, who else?" Die Welt said in its headline, adding that now "her most important task is to groom a successor".
The conservative Frankfurter Allgemeine Zeitung said that as a level-headed and experienced crisis manager, Merkel is still her party's strongest candidate, even if she is "past her zenith at home and abroad".
'Go on the offensive'
Merkel herself was clear that the national election expected next September "will be difficult like no other," as for the first time she will face challengers on both the right and left.
Her current junior partners in the unhappy grand coalition, the Social Democrats (SPD), are flirting with the idea of a leftist alliance with two current opposition parties.
Polls so far would rule out such an alliance - or another scenario where Merkel's conservatives would team up with the ecologist Greens - suggesting that Germany may ultimately return to yet another grand coalition.
The SPD's vice chancellor Sigmar Gabriel is yet to declare whether he will fight his current boss or leave that challenge to another candidate, possibly European parliament president Martin Schulz.
Nonetheless, the SPD's parliamentary leader Thomas Oppermann boldly declared that his party is ready for a good fight, and that Merkel "is no longer invincible".
Germany's top selling Bild daily, usually a strong Merkel defender, had some tough advice for her, predicting the looming campaign "will be her hardest yet" and decided by mainstream voters, "not editorials in The New York Times".
"She needs to go on the offensive," the daily said. "This one is about her - it's her endgame."
By Frank Zeller