The people of Britain made their decision by a slim majority of 52 per cent to 48 percent to Leave the EU. After months of heart-wrenching debates and all the leverage that the Remain side with the Prime Minister David Cameron and his opposite, the Labour leader Jeremy Corbyn, could apply, the people decided staying within the EU was not positive for Britain’s future.

The referendum’s outcome throws Britain into a period of economic and political uncertainties that the Remain side vigorously pushed as their main argument for staying within the EU. There will be a lot of soul-searching among the British elites in politics and business, in the media and in the universities, as to why the opponents of the EU prevailed. The referendum results will be minutely analyzed to understand why the British public was not sufficiently persuaded by their party leaders to back the status quo, and why on the other hand a majority of voters put aside their fear of uncertainty in favor of leaving the EU.

But the overarching reason why Britain left the EU, I believe, is plainly and simply understood if political correctness is set aside. A slim majority of the British public, primarily its aging population who remember what Britain was once like not too long ago as society and culture that open immigration policy severely, if not mortally, has undermined, decided that to save what remained of their island kingdom they needed to regain their full political sovereignty instead of losing more of it to the bureaucrats of the EU in Brussels.

Immigration, it bears repeating, and what it together with multiculturalism have done to Britain in incrementally unraveling its very special place in history, over-rode the arguments in favor of remaining in the EU. The peril of open-door immigration was foreseen many years ahead of the decision made to join the European Common Market (the predecessor to the EU) ratified by a referendum held in June 1975.

Nearly half-century ago Enoch Powell, a Conservative MP and a member of the shadow cabinet led by Edward Heath, spoke out on the perils of open immigration that came to be known as the “Rivers of Blood” speech.

At a Conservative Party gathering in Birmingham on April 20, 1968, Powell warned how unrestricted immigration was inexorably and unalterably changing the nature of British society. What is mostly remembered of Powell’s speech is what was at the time considered inflammatory. But for Powell it was about numbers as he stated, “bearing in mind that numbers are of the essence: the significance and consequences of an alien element introduced into a country or population are profoundly different according to whether that element is 1 per cent or 10 per cent.”

The Birmingham speech ended for Powell a distinguished career in politics as his warnings went unheeded, and he was removed from his position in Heath’s shadow cabinet. In the aftermath of the July 2005 suicide bombings in London, and concerns over “homegrown terror” from radicalized Muslim immigrants or Muslims of immigrant parents born in Britain, Powell’s warning in retrospect was prophetic for contemporary Britain and the West in general.

In the forty years since Britain joined Europe, immigration from the “Third World” countries of Asia, Africa, and the Caribbean have changed her urban landscape. According to Britain’s 2011 census, the foreign-born population constituted 11.9 per cent of the total population. But the cumulative number of the British public as foreign-born, or children of foreign-born, since at least 1961 makes the total in aggregate numbers or in percentage term substantively greater than the 10 per cent of Britain’s population that Powell had warned could significantly alter the character of the country.

It is not immigration alone of people of non-European ethnicity that has had a cumulative impact on the makeup of contemporary Britain. After joining Europe in 1975 Britain, in common with other Western liberal democracies, adopted the policy of multiculturalism as the basis of meeting the demand for equality with the country becoming increasingly multiethnic due to immigration and open borders.

The policy of multiculturalism is based on the spurious idea that all cultures are equal and, therefore, deserving of equal respect and treatment. In effect, this means that the liberal democratic culture of the host country, since multiculturalism as a policy or doctrine is nonexistent outside of the West, is equal to or no better than nonliberal or illiberal cultures of non-Western societies. Hence, multiculturalism is one of the most insidious assaults on liberal democracy based on the hard-won principle of individual rights and freedoms.

In the United States, among those most notable who warned against multiculturalism was Arthur Schlesinger Jr. in his book The Disuniting of America: Reflections on a Multicultural Society (1991). The vulnerability of liberal democracies arises, however, from the situation that the tools by which liberals have advanced the principles of individual rights and secured them in law are equally available -- and indeed, often provided for by liberals as a matter of principle -- to those who either do not believe in liberal values or subordinate them to collective rights based on the arguments of group identity. The demand by vocal segments of the Muslim community for the acceptance of Sharia provisions by Western governments is, consequently, a logical outcome of multiculturalism adopted as a policy of treating equally people of different cultures within a liberal democracy such as Britain.

Such demands as acceptance of Sharia provisions, which have been incrementally conceded in Britain, might be ridiculous to the majority population of the host country. But for the British elites, the absurdity would be in denying the implicit logic of multiculturalism that they concocted and sold to the people.

The absurdity inherent in multiculturalism might be noted in the example of Bikhu Parekh, appointed to the House Lords in 2000 by then Prime Minister Tony Blair. Blair made Parekh, a professor of race relations and of Indian origin, a life peer to secure ethnic Indian votes for the Labour Party. Parekh on his part went on to suggest that Britain should change its name because of the negative connotations for millions of people around the world and, moreover, since Britain has become increasingly multicultural, there remains no justification for it to be British anymore.

Open-door immigration and multiculturalism might also be viewed as the response of Western liberal democracies driven by a sense of guilt for past wrongs. This sense of guilt is uniquely a Western phenomenon, making liberal democracies vulnerable to claims of past injustices made by others, especially non-Westerners who were once ruled by European powers.

The French political philosopher Jean-François Revel observed, “Democratic civilization is the first in history to blame itself because another power is working to destroy it… What distinguishes it is its eagerness to believe in its own guilt and… is zealous in devising arguments to prove the justice of its adversary’s case and to lengthen the already overwhelming list of its own inadequacies.”

In the post-referendum analysis to come of the vote in Britain for leaving the EU, it is unlikely that the issues of immigration and multiculturalism will receive due attention. These are sensitive issues, and there is a legitimate place for politeness -- distinct from political correctness -- when discussing sensitive issues in public.

But if the elites in Britain, and elsewhere in the West are not to get too disconnected from the public, they will need to be honest with themselves and understand how the twin policies of immigration and multiculturalism have divided their societies. It will be a tragic mistake to interpret the vote to leave EU by the British people as a populist and nationalist movement tinged with “white” bigotry.

Instead the Leave vote in this referendum was driven in some measure by the very respectable desire of the British people to demand a halt to the irreversible diluting of their national culture, rich in history and about which they have every right to be genuinely proud, by increasingly conceding to elite-driven policies of immigration and multiculturalism.

To equate a culture that has given to the world Shakespeare and Newton, the Magna Carta and parliamentary democracy, ruled the waves and defended freedom when it was most imperiled, with cultures that practice slavery or gender inequality or impoverishes the human mind, is demeaning. But in the post-9/11 world the British people, though they are not alone, have patiently suffered some living in their midst who take a pathological pleasure in insulting their hospitality, threatening their security, engaging in terrorism and openly espousing causes or doctrines at war against deeply embedded values of freedom and democracy cherished by them.

Melanie Phillips, a British journalist, described in her book Londonistan how greatly, and not for the better, immigration and multiculturalism have changed her country. It should be a matter of pride and celebration when Sadiq Khan, born to Muslim immigrants from Pakistan, is elected the Mayor of London. This could only have happened in the contemporary West.

But if there comes a moment when immigrants from Pakistan, or India, or Nigeria and elsewhere, such as Bikhu Parekh, on the basis of multiculturalism push to turn large portions of Britain into cultural enclaves of their origins, then the tipping point of tolerance for diversity, or pluralism, on the part of the host population has been reached.

The Leave EU win in the referendum was brought about as a result of the tipping point reached by the people in Britain.

Salim Mansur teaches at Western University in London, Ontario and is the author of award-winning Delectable Lie: a liberal repudiation of multiculturalism