Thursday here in Athens, the town where democracy began, saw the final day of a three-day gabfest called the Athens Democracy Forum, where a suave Jordan Bardella of France’s National Rally sat down for a chat with the New York Times star, Roger Cohen.

Was it a case of opposites attract? Oui et non. The head of the foundation that organizes the annual parley, Achilles Tsaltas, prefaced the unlikely pairing by telling participants that “in the spirit of democracy and dialogue , sometimes we invite speakers with whom we disagree — with whom we strongly disagree.”

Mr. Bardella took that measured introduction in stride as he told the audience that he does not want his country, the aforementioned France, to “disappear.” He prefaced that concern by saying that Europe is a continent of 450 million people while due south Africa is a continent of more than one billion. 

“Africa is undergoing a demographic explosion,” Mr. Bardella said.  “We know that migration flows in Europe are a source of worry for a number of people and a number of parties. I believe that this issue must be tackled and that I have the right to question the immigration policies of my country without being labeled as  extreme right or populist or whatever.”

Just days away from the first year anniversary of the massacre that Hamas perpetrated against Israelis, Mr. Bardella also evoked the crisis in the Middle East. “As Israel has seen,” he said, “there exist  people with the same radical Islamic ideology as appears in France, those that want to impose on French society something that is totally foreign to our country, to our values.”  There are, he added, “many French citizens who are Muslim and who fully respect our laws and our habits, but many do not.”

When Mr. Cohen asked, “A lot of people believe you are xenophobic and ultranationalist, have you put away your party’s past?” the telegenic 29-year-old Frenchman didn’t skip a beat. “I don’t think a political party in France can receive 37 percent of votes by being anti-Islamic, antisemitic, xenophobic, et cetera,” he replied.

“I was born in 1995 and I feel nothing in common with Jean-Marie Le Pen and his ideology,” he said, referring to the founder of the earlier iteration of the National Rally known as the National Front, “All political parties have the right to evolve, this is what we have done.” 

He recalled that France “had a Socialist,  President  Mitterand, who was elected in 1980 and served until 1987, who came from the Vichy regime and Maréchal Pétain, people who collaborated with the Nazi invaders. So that evolution was acceptable and ours isn’t?”

“I must have the freedom to criticize the immigration policy of the current government without being labeled xenophobic,” he said. And criticize it he did.

“When you’re a foreigner in a country and you commit a crime, you should be sent back home,” he said. “This is not about deportations, but rather expulsions. According to the ministry of the interior we have 600,000 persons that are in France illegally. I don’t think you can accept people who have violated the laws of our country by coming. We cannot abide that they will receive state aid or support.”

Mr. Bardella said that according to the ministry of the interior, close to 90 percent of violent criminal offenders in France are foreigners. “Clearly not all foreigners are criminals, but if we cannot manage the migrant flows than it leads to more crime, he said, adding that “we need to bring safety and order — the order that General de Gaulle promoted — to French society. I don’t think that looking plainly at the statistics means that I have extreme views.”

Mr. Bardella and Marine Le Pen, a three-time presidential contender who is now the parliamentary party leader of the National Rally in the Assemblée nationale, are the new kingmakers in French politics, and to a certain extent European politics. The math is in the party’s favor — while a loose left-wing coalition, with 142 seats, has more seats in the Assemblée, no actual party has more than the National Rally. 

That means the party can rock the fragile political order at Paris when it sees fit. It is now uniquely positioned to table a motion of no confidence in the government, and President Macron knows it. To placate the National Rally  and to delay a censure motion, Monsieur Macron appointed a prime minister, Michel Barnier, who is already taking a tougher line on immigration than his predecessor. The new interior minister, Bruno Retailleau, is even more to the right than Mr. Barnier. 

At Athens, Mr. Bardella said that when he and Ms. Le Pen met with Mr. Macron in late August to discuss the appointment of a prime minister, he told the president that the National Rally would not be an impediment but that he had a red line: find one who would respect the strong showing of the National Rally. “I’m fed up of seeing the people who vote for us treated as second-class citizens,” Mr. Bardella said on Thursday. 

“I believe that in France, in order to govern you have to lose the elections  — it is a strange situation. We were obviously the first in [the election] results but the alliance between Emmanuel Macron and the extreme left does not allow us to actually govern.”

Not yet, anyway. He added that “I don’t think this situation can last much longer.”  That follows his comment last month that Mr. Macron’s new government would have “no future.”

“What is quite clear,” he said, to the palpable dismay of some of the so-called progressives watching this energetic son of Italian immigrants in the shadow of the Acropolis,“is that nothing in France can be done without us.”