Having led a government that lasted 836 minutes, Sébastien Lecornu has now become prime minister of France for the second time in a week, without it being clear why his chances of success might be greater this time.

After delaying the appointment until deep into the evening on Friday, President Emmanuel Macron again asked Mr. Lecornu, a close centrist ally, to form a government, in what appeared to be an admission that he had run out of options.

“One has the impression that the more he is alone, the more rigid he grows in his initial position,” Marine Tondelier, the leader of the Green Party, said after she attended a meeting on Friday between Mr. Macron and the leaders of several parties.

France, a nuclear power and one of the five permanent members of the United Nations Security Council, has a certain idea of itself. It is not that of a country whose last government survived for less than a day. The descent of the nation into tragicomic turmoil has caused widespread alarm and allowed Mr. Macron’s chief rival, the far-right leader Marine Le Pen, to deplore a “desperate, pathetic spectacle.”

She wasn’t alone in her censure, as a torrent of criticism met Mr. Macron’s choice. Mr. Lecornu will restart his efforts to form a government in a country in a state of severe institutional crisis, tethered to a president who after more than eight years in power has never been so isolated or scorned.

“Lecornu II is a bad joke, a democratic ignominy and a humiliation for the French people,” said Jordan Bardella, the popular president of Ms. Le Pen’s anti-immigrant National Rally party. She wants Mr. Macron to dissolve a deadlocked Parliament and call legislative elections in which her party could well gain enough seats to form a government.

Mr. Macron’s conduct this year in selecting, from a weak position, three prime ministers from his own centrist or center-right camp — the third of them for a second time on Friday — has appeared increasingly incomprehensible, culminating in calls from exasperated former allies for him to explain his stubbornness or resign.

Worried that his economic reforms, including raising the retirement age or cutting the corporate tax rate, might be reversed, Mr. Macron has refused to reach out to the center left, despite the fact that a now frayed alliance of left and far-left parties won more seats than any other group in the 2024 legislative elections.

Rather, with fewer votes he has attempted to exercise more power.

This stance has been widely viewed as showing contempt for the people’s will, never a comfortable position in France.

When Gabriel Attal, once Mr. Macron’s protégé and his choice for prime minister in early 2024, declared this week, “I no longer understand the decisions of the president,” and said that these choices betrayed a “kind of furious pursuit of the maintenance of his power,” he expressed the dismay of many French people.

“We are clinging on perilously between a political crisis and a crisis of the regime, where either we have a government so fragile it could fall any day, or parliamentary elections that will certainly hand victory to Ms. Le Pen,” said Alain Duhamel, a prominent author and political analyst.

As president, Mr. Macron has certain powers, including those of selecting a prime minister and dissolving Parliament to call a legislative election. But he does not have a majority in the National Assembly, the lower house. He no longer has a loyal centrist party of his own. His ideology, known as Macronism, a mélange of shifting ideas once intended to overcome a left-right cleavage, has collapsed.

In short, now in the last 18 months of his term-limited rule, Mr. Macron is weak, even if still influential internationally.

A poll by Elabe, published this week in the business daily Les Echos, showed his support collapsing to 14 percent of the electorate, the most unpopular he has been and one of the lowest approval ratings ever for a French president.

Yet Mr. Macron’s decisions have offered no concessions or readiness to change methods, as was further illustrated in his decision to reappoint Mr. Lecornu. With the far-right National Rally and far-left France Unbowed parties implacably opposed to him, and the center-left Socialists and conservative Republicans also unhappy with Mr. Macron’s choice, it was unclear how any second Lecornu government could last long.

Mr. Macron “needs a parliamentary majority to support him,” Denis Baranger and Olivier Beaud, two professors of public law, wrote on Friday in the daily Le Monde. “Because he has not understood this reality, Mr. Macron is now totally isolated and has thrown the country into an unprecedented institutional impasse.”

It appeared to be Mr. Macron’s insistence that Bruno Le Maire, a former finance minister now being blamed for the rise in French debt to $4 trillion, become the defense minister in the ephemeral first government of Sébastien Lecornu that caused it to blow apart in less than a day this week.

Mr. Le Maire is close to the German chancellor, Friedrich Merz, a relationship that Mr. Macron viewed as important given the need to integrate European military power at a time of war on the continent. But the surprise choice proved intolerable to Bruno Retailleau, the right-wing interior minister, who had been blindsided and promptly sounded the death knell of a government Mr. Lecornu had spent almost a month assembling.

It was another example of the repetitive fiascos now afflicting France.

These have followed Mr. Macron’s still unexplained decision to call parliamentary elections in June of 2024. He was under no obligation to do so. Since then, the National Assembly has been split three ways among the nationalist far right, the left and the far left, and an enfeebled center whose loyalty to Mr. Macron is fading.

This Parliament is dysfunctional; that much is proven. But France needs a budget to confront its mounting deficit and debt.

In theory, Mr. Lecornu must present the budget next week if it is to be approved by the end of the year. With the current parliamentary configuration, it is difficult to see how he will get the budget passed — or, if he somehow does, how his government will survive much beyond that.

Yet Mr. Macron does not want to dissolve Parliament and perhaps finish his presidency with Mr. Bardella as his prime minister.

For 80 years, since the end of World War II, France has prided itself on keeping the far right from power after the shame and humiliation of the Vichy Government that collaborated with the Nazis.

“This is not going to end well,” Ms. Tondelier, the Green Party leader, said.