It’s an increasingly hard world for those seeking a better life in richer countries. Immigrants aren’t welcome in most states, even where demographic trends reflect the need to expand the labor force to levels able to sustain and support aging populations.

While both Europe and the United States will have to face the need for younger workers in the coming decades, citizens in the wealthy nations, no matter what their ethnic backgrounds, dislike mass immigration and punish politicians who allow it.

In Europe especially, immigration is the main driving force for nationalism, for the rise of populist parties and for the decline of the center left.

There are exceptions. Spain, which has had relatively low immigration from North Africa, accepted over 600 migrants from a stranded ship, the Aquarius, that Italy and Malta had turned away. Ireland has been notably more sympathetic than most to the plight of Syrian refugees (though substantial minorities there worry about strains on health and welfare systems.) The devolved administration of Scotland – concerned about its aging population and shrinking work force – has for some years proclaimed itself more welcoming to immigrants than the British government in London.  

But the movement remains towards exclusion. In Germany, Europe’s leading economy and most powerful nation, Chancellor Angela Merkel differs sharply with her Interior Minister, Horst Seehofer, on the latter’s call to block migrants already registered in another EU country from entering Germany.

Seehofer is chairman of the Bavarian Christian Social Union, in what has been a permanent coalition with Merkel’s Christian Democrats. The CSU has given her till early next month to come up with a compromise; most Germans presently believe she will fail to do so. Such a failure would endanger her coalition government, but the CSU is hard-pressed by the anti-immigrant Alternative for Germany (AfD) ahead of October state elections in Bavaria and can’t afford to back away from its threat to unilaterally close German borders.

Merkel hopes to find an EU-wide agreement. An "informal meeting" of several leaders – including those from Austria, France, Germany and Italy, chaired by the EU Commission president Jean-Claude Juncker – will take place Sunday to seek some form of agreement before a June 28-29 EU summit – a sign that the issue now dominates the politics of all of them.

Merkel’s closest EU ally, France’s President Emmanuel Macron, has himself hardened his stance on migrants, telling Italian Prime Minister Giuseppe Conte that those requesting asylum should be handled by centers established outside of Europe. Macron framed it in humanitarian language, saying that it’s not right for those with no chance of getting asylum in Europe to die in the Mediterranean or live in “unworthy” conditions, but his proposal would mean that France follows Italy in banning entry to migrant ships. At the same time, however, France criticized Italy’s decision to refuse permission for the Aquarius to dock – and accepted some of the migrants on board.

Insofar as there is European agreement on immigration, it is coming from the anti-immigration wing of the Union. Earlier this week, a meeting between Germany’s Seehofer and Austrian Chancellor Sebastian Kurz produced an agreement to create an “axis,” not so much, as Kurz put it, “of the willing,” but of those states – including Germany, Italy and Austria – unwilling to accept more migrants. Merkel is thus challenged not only by Italy, whose new populist government sees her insistence on open borders coupled with pressure to cut Italian public spending as intolerable, but also by her ally Macron, by her neighbor Austria and by her own interior minister.

This toughening stance begins to move the Western European EU members closer to the Central Europeans – the Czech Republic, Hungary, Poland and Slovakia – all of which have refused to take the quota of migrants decided for them by the EU. In a powerful essay, Branko Milanovic, a former economist at the World Bank, argues that for these states, liberated from communism and control by the Soviet Union (and before Moscow, from the Austro-Hungarian empire), are deeply opposed to a migration which would dilute their ethnic homogeneity and new-found national freedom. Milanovic writes that “ethnic heterogeneity would… come from within in the form of migrants, people of different culture, religion, and most scary in the eyes of the locals, people whose birth rates significantly outstrip the anemic, or even negative, growth rates of the native population. Migration thus appears as a threat to the hard-won national independence.”

In many minds, “threat” is now an indivisible companion to “migrant.” To opponents, the new arrivals threaten crime; a dilution of national ethnicity and a claim on services paid for by the taxes of the native population. Europeans especially don’t like immigration of Muslims, fearing the new arrivals might include militants planning acts of terror.

The advantages of a young and usually hard-working cohort who will themselves pay taxes, take jobs no longer attractive to existing citizens and provide cultural diversity are either less visible or increasingly ignored. In France, the Malian migrant Mamoudou Gassama, who climbed up to a fourth-floor balcony to save a four-year-old child in danger of falling, was granted French citizenship and time with President Macron for an act of courage – an opportunity unlikely to come the way of others seeking nationality.

U.S. President Donald Trump is one who sees migrants all but wholly through the prism of “threat.” He is unremittingly harsh, using terms like “infest” and “animals” in his references to those trying to enter the United States without documentation. His enforcement of a policy that led to children being separated from their families at the U.S.-Mexican border was widely seen, even in his own Republican Party, as an abomination, and – after falsely accusing Democrats of being responsible for the policy – he signed an order ending the separations.

The pressure of the poor on the rich world is one of the sorriest sights of the past few years. The pressure will not go away; neither will the resistance to it. Africa and the Middle East, especially its war zones, will continue to pour forth tired, poor and huddled masses, and they will continue to be pushed back. Leaders, liberal and conservative, will have little choice but to join the push-back party if they wish to remain in office.

These leaders must now get smarter – rather than more reactionary. The poverty and conflict that increasingly divides the world must be addressed more comprehensively than it has been so far. The effects of its misery can no longer be confined within poorer borders: it more and more becomes the rich world’s emergency too.

(John Lloyd co-founded the Reuters Institute for the Study of Journalism at the University of Oxford, where he is senior research fellow. Lloyd has written several books, including “The Power and the Story”” and “Journalism in an Age of Terror”. He is also a contributing editor at the Financial Times and the founder of FT Magazine.)

Editor's note: This column has been updated to correct the description of Branko Milanovic's former position at the World Bank.