RUTHFULLY YOURS

Nanterre, France

Following last week’s terror attacks in Paris on journalists at the satirical newspaper Charlie Hebdo and on a kosher supermarket, many Western leaders have been reluctant to say the motive was at all religious. French President François Hollande said Charlie Hebdo had been targeted by “obscurantism,” whatever that is. And White House spokesman Josh Earnest on Tuesday spent a painful five minutes explaining the Obama administration’s aversion to using the term “radical Islam.”

That’s not a problem for Marine Le Pen, who is never obscure.

“It’s clear Islamic fundamentalism,” says the leader of the National Front, France’s far-right political party that has been gaining in the polls. “Now all the eyes are open,” she adds, referring to a general French awakening to the Islamist threat. And “we are the only ones to solve the problem,” by which she means the National Front.

Once a political outlier, Ms. Le Pen has been gaining prominence as France’s problems—a moribund economy and its un-assimilated Muslim-immigrant population—have become more acute and seemingly beyond cure by the traditional political class. Now, in the aftermath of the home-grown Islamist slaughter in Paris, Ms. Le Pen is betting that she is the French politician most likely to benefit from her countrymen’s shock and disbelief over the threat in their midst.

So it seems a good moment to visit with Ms. Le Pen, whom I met Friday at the National Front’s headquarters in Nanterre, a northwestern suburb of Paris. National Front posters with the slogan “Oui, la France” depict a fierce woman with steely eyes, and that she is: a tall, commanding presence who speaks rapidly in a husky rumble of a voice. But the 46-year-old Ms. Le Pen, alternately smiling or reserved as the moment requires, is also unquestionably charming. There’s a smile covering the steel.

When discussing the terror attacks, or many of France’s other problems, Ms. Le Pen steers the conversation to immigration. “The first problem is that the borders are open, and practically anyone can go freely all around,” she says. “There is no responsible country that would accept such a situation.” It should have been “obvious,” Ms. Le Pen adds, that “massive immigration would just allow the fundamentalists to increase their numbers.”

Seated with three large French flags on the wall nearby, she adds: “There are obvious signs that among the people coming so easily into our country, the hormones of unrest will rise. The French Republic needs to offer to its forces, police, security and army, the proper means to protect our country.”

Yet Ms. Le Pen balks at the prospect of heightening government surveillance to prevent future attacks: “We are totally for individual freedom. The freedom for all is important. In order to catch some, we should not block everybody.”

At the same time she rejects as too weak the tough new counterterror measures announced by Prime Minister Manuel Valls on Friday—including isolation of jihadists in prison, increased staffing at intelligence agencies and granting security services broader power to monitor online communications. “Valls’s speech,” she says, “it was just a speech.” Beyond restricting immigration, her main counterterror proposal is the construction of new prisons and additional funding for the penitentiary administration.

In a country already made wobbly by years of economic anemia—with unemployment hovering intractably above 10%, roughly one in four young people unemployed, and negligible to nonexistent growth—and now quaking after the eruption of Islamist terrorism, Ms. Le Pen’s blunt-force prescriptions have made the National Front more plausible as a political force than it has ever been. Where the party had been an alarming but relatively marginal player under the leadership of her father, the rhetorical bomb-thrower Jean-Marie Le Pen, the more media-savvy Ms. Le Pen has been better at selling the nationalist line since taking over from him in 2011.

Her fixes for France’s troubles are simple: Exit the European Union and end the reign of “globalist” economics—the free movement of goods, capital and labor—that she blames for the fact that France is “dying.” Above all: “Stop immigration,” not just to discourage the potential Islamist threat, but for the overall health of the country. “There are 200,000 legal immigrants coming to France every year,” Ms. Le Pen says. “They just add to the problems.”

Ms. Le Pen doesn’t directly answer my question about what she proposes to do about the millions of Muslim immigrants whose only nationality is French. Instead, she turns her attention to immigrants with dual citizenship. “Do you know that there are 700,000 voters, Algerian and French, who voted in the recent Algerian elections?” she asks. “These people can and should decide one way or the other. We have nothing against being a foreigner in France, but they have to decide.” The message: Choose France or get out. Also: Those with dual citizenship who commit crimes in France should “be sent back.”

It’s tempting to dismiss these views as unrealistic and against the tide of history—the French political and media establishments routinely do. As Ms. Le Pen says: “Many political parties in France and many in the media, the first question they ask about anything is: ‘Will this be advantageous for the National Front?’ ” A notable example was the decision by the organizers of last weekend’s unity march in Paris not to invite Ms. Le Pen and her supporters.

But merely to dismiss or ignore Ms. Le Pen and the National Front doesn’t deter her political project. She represents a real and substantial constituency of people who, as one Paris-based journalist told me, “don’t recognize the French republic they used to know anymore.” These are working-class voters, mostly white, who once answered the old left’s call of class solidarity but who now feel left behind as manufacturers and job-creators flee the country under the press of France’s rigid labor laws, protectionist rules and high taxes.

When France’s postwar economy was still booming, and the welfare state was cash-flush, the country could afford to absorb millions of Muslim immigrants, mainly from France’s former colonies in North Africa. At the time, lawmakers made almost no effort to encourage these newcomers to assimilate. They were relegated to banlieues, public-housing ghettoes on the outskirts of major cities, where the French republican ethos—liberty, equality, fraternity—rarely penetrated.

Ms. Le Pen says it is too late to bring these immigrants into the mainstream: “You can’t assimilate a group,” she says. “The group will impose the laws of the group on the individual. . . . The French nationality, either you earn it, or you deserve it, but it’s not granted automatically.”

She cites Lassana Bathily, the black Muslim employee of the besieged kosher supermarket who helped save Jewish lives during the hostage crisis, as a model. “It’s good that we gave him the French nationality” after his heroism became known. By contrast, the Kouachi brothers, who perpetrated the Charlie Hebdo attack, “already had a police record, and obviously they should not have been given French nationality,” she says.

Nor does Ms. Le Pen favor a grand bargain with French Muslims, an oft-proposed model in which the French state, which is colorblind according to its founding ideals, gives Muslim immigrants a leg up in exchange for a pledge of allegiance from their communal leaders. “Positive discrimination, this is very bad for France,” she says. “This again was imported from the U.S., and it will never work in France. The grand bargain in France is called secularism. The laws had to be respected by all.”

She adds: “Whom do you talk to in France with the Muslim community? The current major Muslim organization in France, which is privileged nowadays, is linked to the Muslim Brotherhood. Meanwhile, General Sisi in Egypt is fighting the Muslim Brotherhood.”

Under her father’s leadership, the National Front developed a reputation as a party of cranks and anti-Semites. Mr. Le Pen caused a storm in 1987 by calling the Holocaust a “detail in the history of World War II.” Last year he said that “Mr. Ebola” could “sort out” the world’s “demographic explosion.”

Ms. Le Pen has tried to distance the party from her father’s legacy, and she has made a few inroads in the French Jewish community. She says she has been ahead of others in sounding the alarm about anti-Semitism. Muslim fundamentalists, she says, “take advantage of the Israeli-Palestinian conflict. The National Front is the best shield to protect France’s Jewish citizens against this threat. We are the only ones to solve this problem.”

The National Front is by no means a traditional right-wing party. On economic matters, the party is closer to the left. Take the Trans-Atlantic Trade and Investment Partnership, or TTIP, the Euro-American free-trade agreement that analysts estimate would boost growth by $100 billion on both sides of the pond. The environmentalist left and labor unions fiercely oppose the TTIP; so does Ms. Le Pen.

“The U.S. way of conducting business doesn’t bring anything to France,” she says. “The hygienic and social methods imposed in the U.S. are not similar to the needs of France and the French. The multinational interests that impose their own ways are not good for France. Practically, all these are just weakening France. I am in defense of economic ways that would help France.”

Ms. Le Pen also has a soft spot for Russian President Vladimir Putin . “Putin did very difficult work,” she says. “He had to face and put together Russia after the Soviet Union. It’s a complicated country. We should not continue anymore to impose our own ideas and our judgment on the situation in Russia. Putin was able to gain Russia respect and place it again on a high level on the international stage.”

American global leadership is anathema among the National Front crowd. “I am for a multi-polar world,” says Ms. Le Pen, “where each country definitely has its own sovereignty. The economic model suggested by Putin, which is a patriotic model, is positive in my eyes. Russians are patriotic, and this is a welcome thing. We can do nothing against Russia. There is a Cold War now against Russia that France is involved in. We should work with Russia.”

Regarding allegations that the National Front has received a €10 million loan ($11.58 million) from a Kremlin-tied bank, Ms. Le Pen says: “All is false as usual. We went to French banks, many European banks, but all refused our request. The bank in question is not a Kremlin bank but a private bank. This in no way has an influence on the National Front’s political views and that will never change. If a U.S. bank or a French bank would like to lend us money, we would accept gladly.”

The European Union, which even its supporters concede suffers from a democratic deficit, draws her scorn. “I believe in nations,” she says. “I believe in democracy. I believe in people who are in charge of their own destinies. The European Union concentrates all the worst aspects of hyper-socialist ideas and all the worst aspects of the ultra-liberal ideas. The European Union was made against the people’s wills. It is a failed experiment.”

In last May’s elections to the European Parliament, the National Front thumped both the center-right Union for a Popular Movement and the center-left Socialists. In a September poll, Ms. Le Pen beat President Hollande in a hypothetical face-off. France’s next presidential election is still two years off.

Meanwhile, on Thursday police raided an Islamist cell that spread across Belgium and France. Authorities said jihadists were planning to murder police officers in the streets. Two suspects in Belgium were killed. Fifteen suspects were arrested in the two countries—and France shuddered anew.

Mr. Ahmari is a Journal editorial-page writer based in London.

Correction: It is alleged that National Front received a €10 million loan from a Kremlin-tied bank. An earlier version of this story misstated the alleged amount.