In France, the US and many otherwise enlightened corners of Europe, people and politicians are asking an awkward question: Do Muslims belong in the modern nation-state? It's uncomfortable, but it's also timely. Europeans are living in the wake of the largest cross-border migration crisis since World War II, when more than a million mostly Muslim asylum-seekers have streamed into Europe from an increasingly pulverised Middle East. They are also being battered by a seemingly unending spate of urban terror, much of it attributed to members or devotees of the Islamic State (IS) terrorist group. These are not easy times to be visibly Muslim in minority-Muslim countries. In recent weeks, two contrasting approaches to this question have played out through the lens, of all things, of women's clothing. In France, photographs shared on social media of armed police approaching a Cote d'Azur beachgoer in a full-body swimsuit and enforcing a ban on the burkini kicked off a firestorm around freedom, faith and what it means to be French. Despite the ban being overturned by a Nice court a week later, the debate over whether burkinis are acceptable beach wear, and whose decision that should be, rages on. Meanwhile, local police in Canada and Scotland have been offered an official hijab. New policies in the Scottish Metropolitan Police in the UK and the Royal Canadian Mounted Police have introduced hijabs as part of police uniforms. They join the London Metropolitan Police Service, where the hijab has been part of uniforms for more than a decade. A spokesman for Canada's Public Safety Ministry told Canada's CBC TV station that women could wear the headscarf “if they so choose.” The decision, he said, was a reflection of the institution's values. "The Royal Canadian Mounted Police is a progressive and inclusive police service that values and respects persons of all cultural and religious backgrounds.” The point is about belonging. In December, Canadian Prime Minister Justin Trudeau distinguished himself and his country by welcoming Syrian refugees as future citizens and participants in the national project: in his words, “you are home.” His words compared to a tepid European welcome. German chancellor Angela Merkel, dealing with far greater numbers of unvetted asylum seekers, has made clear that Germany expects people to go home when the wars end. Denmark demands refugees hand over valuables in order to benefit from the country's welfare system, and now some Muslim women, born and raised in France, say they do not feel welcome on their country's beaches. These incidents, against the backdrop of social friction across Europe, raise questions about how Muslims from Muslim-majority countries can integrate into Western Muslim-minority countries. On the conservative right, across the US, UK and Europe a growing chorus of voices is telling us they cannot. That Muslims do not belong in a modern, secular nation-state – that integration cannot happen because Muslims are somehow used to living in another kind of state. But this is incorrect. Research shows that 93 per cent of the world's Muslims live in modern states, where central state structures are far more powerful than any non-state structure. Seventy-three per cent of the world's Muslim population lives in states that were once part of European multi-national empires. Iraq, Syria and Afghanistan, three of the Muslim-majority states whose collapses are fuelling the global refugee crisis, are disintegrating in large part due to the universal acceptance of the principle of national self-determination: citizens want a stake in their own political future. National self-determination, then, as it is enjoyed in the West, has had a tremendous impact on the lives of the majority of the world's Muslims. History shows that when people are denied self-determination, they fight for it. So why are so many modern nation-states limiting the stake new arrivals can have in their own future? Or, looking to the past few weeks, why are nervous government officials forcing women to take off the burkini in the name of integration or assimilation? The well-being of a society depends on its composite members identifying as belonging to that group. In a pluralistic democracy such as Canada or the UK, this means facilitating the feeling of being Canadian, as much as being Muslim, Arab or of Syrian or other descent. Canadian and Scottish police officers can wear hijabs because doing so does not preclude membership in the nation-state project or that country's law enforcement service. Beneath this context is an even more important subtext. The face of Canadian and Scottish policing may be Muslim, as may be the faces of those being policed: Muslims are part of Canadian and Scottish society. On balance, there is seen to be more to gain by permitting female service members to wear the hijab, than there is to outlawing such an expression of religious identification. Through this lens, inclusive nation-building – for all members of society – offers a means to make state and people one. By facilitating the participation of all members of society in communities, civil society and politics, officials can ensure that the culture of their state matches that of its citizens in their totality. Looking to the beaches of southern France, there are two ways to read the message: Either Muslim women don't belong here – even if they are French citizens – or they are tolerated, provided they check visible manifestations of their faith at the door. Neither of these messages promotes an inclusive nation-state. Both run the risk of leading to exclusion and further division. In France and Belgium an outcome of a nation-state failing to include a generation of Muslim immigrants can be seen: disenfranchised young people born as citizens, but belonging to Paris's banlieues or Brussels' Molenbeek district, isolated from mainstream employment and opportunity, grouped together in an insignificant backwater far from the centre. The roots of supra-national extremist belief find fertile ground here. The writer is director of the Aga Khan University Institute for the Study of Muslim Civilisations (AKU-ISMC) in London.