In the wake of the London attack, western leaders are insisting that all Europeans share the same values. The uncomfortable reality is that it isn't true.

Speaking at a vigil on Monday for the victims of the recent terrorist attack in London, Mayor Sadiq Khan had a message for the “sick and evil extremists” out there: “As a proud and patriotic British Muslim, I say this: you do not commit these disgusting acts in my name.”

That drew polite applause. He went on, as if to leave no doubt that whatever else the attackers were they were not true Muslims: “Your perverse ideology has nothing to do with the true values of Islam,” adding that a united London stood in defiance of an attack on “our values and our way of life.”

We’ve come to expect such talk from western political elites when they’re confronted with the brutal reality of homegrown Islamist terrorism. But behind these banalities is the great conceit that “western values” are universal. Khan and his milieu are fond of pretending that all Muslims in Britain have more or less the same “values and way of life” as the concertgoers who were blown up last month in Manchester, or the crowds that were attacked while drinking at pubs in Borough Market on Saturday night.

It is not polite to say so, but this is simply not true. Although they might be a minority, a not insignificant number of Muslims in Britain and across Europe do not share Khan’s values or his ideas about Islam. Their numbers and influence is of course a matter of debate, but it is long past time for European leaders to admit that western values are not universal.

If—and it’s a big if—Europe’s political leaders really want to do something to stop these attacks and not simply learn to live with them, they will have to face the reality that many of their own citizens do not much care for western values. And they will have to consider what it might require to address that reality in the years to come.

Not All Muslims Think Like Mayor Khan

On Monday, British officials named two of the three London bridge terrorists: Khuram Shazad Butt, a 27-year-old British citizen born in Pakistan, and Rachid Redouane, a 30-year-old whom police said claimed to be Moroccan and Libyan.

It appears that these men were Muslims—or at least they considered themselves to be Muslims, Khan’s disapproval notwithstanding. Butt was reportedly a member of a group called al-Muhajiroun that supports ISIS and wants Britain to become a Muslim nation. Both men were followers of the radical British cleric Anjem Choudary, who was sentenced to five years in prison last year for supporting ISIS, and according to one neighbor, Butt’s wife wore a face-covering niqab.

Accounts of the attack seem to confirm the terrorists’ motive. The mother of one of the victims told the press that her son had stepped outside the bar when a man ran up to him and said, “This is for my family. This is for Islam,” and stuck a knife in him.

In her remarks Sunday, Prime Minister Theresa May tried her best to speak candidly, saying that Britain “cannot and must not pretend that things can continue as they are.” She’s right about that, and also right that Britain is far too tolerant of extremism (although, like Khan, no mention of what kind of extremism). Stamping it out, she added, “will require some difficult, and often embarrassing, conversations.”

That last phrase is telling. The only possible reason confronting “extremist” views might be embarrassing is because so many British Muslims hold such views—and the prime minister knows it.

Although it’s true that a majority of British Muslims don’t hold extremist views, a sizeable minority don’t exactly hold western views, either. Polls bear this out. Last year, an ICM poll examining the attitudes of British Muslims found that more than half think homosexuality should be illegal. Almost half said they didn’t think it was acceptable for a gay person to be a teacher, nearly a quarter believe that Sharia law should be introduced in some parts of Britain, and 39 percent agreed that “wives should always obey their husbands.”

While some conservative Christians might agree with that last bit, being a fundamentalist Christian doesn’t entail the same sort of beliefs and practices as being a fundamentalist Muslim—things like female genital mutilation and honor killings, both of which are on the rise in Europe (PDF).

As Europe’s Muslim population grows, so grows the ranks of those who adhere to a strict interpretation of their faith, more akin to the way Islam is practiced in the Middle East, Africa, and Asia. A survey of 9,000 Europeans published in the Journal of Ethnic and Migration Studies in 2015 found that Islamic fundamentalism is not a marginal phenomenon in Europe. The study’s author, Ruud Koopmans, defined religious fundamentalism in three ways: 1) believers should return to the eternal and unchangeable rules laid down in the past; 2) these rules only allow one interpretation and are binding for all believers; 3) religious rules should have priority over secular laws.

The study looked at Turkish and Moroccan immigrants and the children and grandchildren of such immigrants, as well as native European Christians. Based on the study’s parameters, “between 40 percent and 45 percent of European Muslims have fundamentalist religious ideas, that is they agree with the three definitions of the term,” said Koopmans.

The survey found that if each definition is taken individually, across the first and second generations almost 60 percent say they would return to the roots of Islam, 75 percent believe there is only one possible interpretation of the Quran, and 65 percent say that religious rules are more important to them than the laws of their home country. Compare those results to the Christians surveyed, only 4 percent of which agreed with the three definitions of religious fundamentalism.

How Much Do We Really Believe In Western Values?

European leaders know all this. The former head of Britain’s Equality and Human Rights Commission said the findings of the ICM poll were “extremely worrying” and suggested that on many issues British Muslims are a “nation within a nation.”

None of this means that most European Muslims hold radical views or support ISIS. But it does mean that empty slogans about how all of Britain is united are not going to address the problem that the prime minister tried to address in her remarks on Sunday: that Islamic extremism has been given room to breathe in Britain.

The fact is, many thousands of Muslims in Britain, as well as Muslims throughout Europe, do not share what Prime Minister May and Mayor Khan and the rest of the political elite consider to be universal western values. It is uncomfortable, even embarrassing, to admit to ourselves that a great many Muslims in Britain and Europe do not much care for the West as such. Things like gay rights and women’s equality and free speech and the rule of law simply do not demand their respect. They do not cherish western culture or seek to preserve western traditions. Their allegiances lie elsewhere.

It is even more embarrassing to admit that we westerners do not much care for these things ourselves anymore—at least not enough to demand that our fellow countrymen, regardless of religion and creed, adopt them and teach their children to revere them. Until we start demanding that kind of unity, Muslim extremists will have room to breathe in the West.