Born in Pakistan and educated in the US, Mohsin Hamid has made a home in the UK. He explains why he longs for a world without borders

I believe in a human right to migration, as fundamental as the right to freedom of expression, or freedom from discrimination on the grounds of gender, race, religion or sexuality. I have come by this belief by migrating myself. (I’m inclined to prefer the terms migrant and migration to immigrant and immigration: the latter two seem to privilege the country of arrival; every immigrant is also an emigrant, and migrant encompasses both.)

I was born in Pakistan. And I live in Pakistan. But when I was three I moved with my parents to Silicon Valley in California. I returned to Pakistan when I was nine for a decade, then spent most of my 20s on America’s east coast and most of my 30s in London. I possess a British passport and once possessed an American green card.

My life has come full circle, geographically speaking. Twice.

Most of my education has been in the American system. I suspect this has contributed to my discomfort with a great deal of what I see practised around me in Pakistan. I have friends who are non-Muslim; non-Muslims are legally persecuted here. I have friends who are gay; homosexuality is legally proscribed here. An African friend once told me after visiting that Pakistan was among the most blatantly racist places he had ever been. Pakistani laws discriminate against women. Pakistani courts fail to deliver any semblance of due process. Pakistani presidents are frequently unelected generals. My largely American-educated self is continually brimming with disappointment.

Yet my largely American-educated self is profoundly disappointed by America, too. This is partly because the US’s bellicose excesses in foreign policy become more visible the closer you are to where American bombs are hitting the ground. But it is also because I studied American history with American teachers and American law with American professors.

From them I learned about manifest destiny, the notion that Americans were destined to migrate west until they had settled the entire continent; about the melting pot, uniting people of all races, ethnicities and creeds into one nation; about a country of immigrants, with this poem by Emma Lazarus inscribed at the base of its Statue of Liberty:

Not like the brazen giant of Greek fame,

With conquering limbs astride from land to land;

Here at our sea-washed, sunset gates shall stand

A mighty woman with a torch, whose flame

Is the imprisoned lightning, and her name

Mother of Exiles. From her beacon- hand

Glows world-wide welcome; her mild eyes command

The air-bridged harbor that twin cities frame. “Keep, ancient lands, your storied pomp!” cries she

With silent lips. “Give me your tired, your poor,

Your huddled masses yearning to breathe free,

The wretched refuse of your teeming shore.

Send these, the homeless, tempest- tossed to me,

I lift my lamp beside the golden door!”

Migration and equality are intertwined at the heart of the US’s story of itself. As the vast migration to America continued, this story goes, the equality offered by America grew. So it was that the US Declaration of Independence could declare only “that all men are created equal”, but a century and a half later, women too would be granted the vote. So it was that the US Constitution could openly tolerate slavery, but within one century slavery would be outlawed – and within a second some of slavery’s most toxic residues would be partially mitigated by the famed civil rights movement of the 1960s, the decade before my birth.

And yet, in my lifetime, as someone who has often lived in America, I could see, more and more, a new category of person there, neither slave nor free. They were everywhere and they numbered in their millions: illegal immigrants. How, I wondered, was such a thing possible? Surely all Americans were immigrants. Yet legally, it now seemed, not all immigrants were Americans, and as the caste of “illegals” swelled in the closing years of the 20th century and initial years of the 21st, the overall inequality of American society began to grow, too.

If the US distances itself from the human right of migration, the tenor of the dominant story of America changes. For America’s story is also, frighteningly, a story about the genocide of the pre-Columbian population, a story about the importation of disenfranchised underclasses, initially from Africa and more recently from Latin America, and a story about the quest for unrivalled economic and military dominance around the world.

Such a revised story sits uncomfortably with those equality aspiring institutions that America already has. This has inevitably led to a crisis. And this crisis helps explain why America is flailing today: America has become incoherent. An America that denies the human right of migration can no longer be the America it imagines itself to be, because it can no longer champion equality. It can no longer claim to be exceptional. It can no longer believe in being its own best self.

America’s greatest hope lies where it always has: with the homeless, tempest-tossed to that golden door.

And migration is the half-forgotten core of Britishness as well. I migrated to the UK 13 years ago, not expecting to remain long. I thought I would experience London for a year, then return to New York. But I found London remarkably open to migrants, to dissent, to creativity. I stayed for the better part of a decade, becoming a naturalised citizen in the process. I made a home for myself in Britain, wrote a novel there, worked in business there, got married there, had a child there. Anti-migrant sentiment was always present, but for a while in the early noughties it seemed it was waning, that a new, more cosmopolitan Britain was being born.

Alas, times have changed. Sovereignty seems to be the rage in Britain these days. But this sovereignty, at its heart, is imagined not merely as more rights for people in Britain, but as more rights for those whose ancestors have been in Britain longer. In nativist-sovereign Britain, the plumber of Bulgarian citizenship is a plausible candidate for expulsion. In nativist-sovereign Britain, the British woman with Bangladeshi parents is a problem to be solved.

Surely the dangers of such an outlook are self-evident. What becomes of Northern Ireland under such a concept of sovereignty? What becomes of Scotland, which has been ruled from London for less time than England has? What of the migrant-peopled dominions of Gibraltar and the Falklands? Treating nativist sovereignty as a virtue, and migration as a crime, threatens to make the United Kingdom dysfunctional.

For Britain, too, is a land of migration, indeed of extreme migration. Without migration, the human population of these and all other islands would be zero. Without migration, the English language would not exist. There would be no Commonwealth without migration – no Canada, no Australia, no New Zealand – for without migration there would have been no empire. And without the British empire there would be precious little of the accumulated wealth and knowledge underpinning the industries on which the British economy is now based.

But as a British person who reads the press of my own (British) country, I encounter a sadly predictable narrative. It sums up the last couple centuries of world history as follows. When a Briton goes abroad, he or she is a hero. When someone else tries to come to Britain, he or she is a villain.

It is not a take on history that suggests future greatness. It suggests instead a retreat into fear and insularity. It deserves more robust challenges than it has received thus far. The deepest threat Britain faces comes not from migration. It comes from the relentless transfer of wealth and opportunity from the poor and middle class to the wealthy, a transfer masked and rendered temporarily palatable by the chest-thumping of resurgent nationalism and the paper gains of credit-fuelled property prices.

Britain and America are by no means unique in denying the human right to migration. All wealthy democracies do much the same. China and some other countries even restrict the migration of their citizens within their own borders.

This problem must be addressed. The scale of migration we will see in the coming centuries is likely to dwarf what has come before. Climate change, disease, state failure, wars: all these will push hundreds of millions, perhaps billions, to leave one country for another. If we do not recognise their right to move, we will be attempting to build an apartheid planet where our passports will be our castes, and where obedience will be enforceable only through ever-increasing uses of force.

There is another way. We can recognise the human right to migration. We can recognise that we are ourselves, all of us, doubly migrants. We are migrants historically: our ancestors came from somewhere else, and originated, long ago, in the same spot in Africa. And we are migrants personally: life is the experience of moving through time, of abandoning each present moment for the next, of temporal migration.

Acknowledging this, we can accept that we have no right to forbid or stigmatise migration. We have only the power to try to do so. And we ought to endeavour to use that power as little as we can manage, less and less over time, for we are using it to deny the human rights of others. It is we, those who stop migration, who are the criminals, not those who are migrants. And slowly, at a pace that does not terrify us, but whose direction is clear, we must gradually let go, and allow things to change. Only in doing so can we hope to build a world in accordance with the values we claim to believe in – liberty, equality, democracy – and wash clean the taste of hypocrisy that burns so bitter in so many of our mouths.

I imagine that centuries hence, when people are finally free to move as they please around the planet Earth, they will look back at this moment and wonder, just as we wonder about those who kept slaves, how people who seemed so modern could do such things to their fellow human beings, caging them like animals – merely for wanting to wander, as our species always has and always will.

Mohsin Hamid’s Discontent and Its Civilizations: Dispatches from Lahore, New York and London is published by Hamish Hamilton on Thursday at £16.99.