How borders are drawn and enforced has far-reaching consequences, whether we live on either side of them or halfway across the world.

We’ve been led to assume that the world of our children would be a place of fewer borders and lower barriers to the movement of goods and people. Not long ago, walls were literally brought down, with the promise that global progress and prosperity would henceforth be marked by openness.

That’s not how things are trending now, and the consequence is troubling for those of us who believe that the most powerful cure for war and economic stagnation is direct exchanges between people around trade and ideas.

The latest signal of rising barriers is the European Union considering in the coming days whether to require visas for US and Canadian tourists who currently enter without the extra hassle. It’s a discussion prompted by those countries’ own obstinance about extending the same courtesy to citizens of all EU member states.

An enthusiasm for erecting barriers is evident elsewhere, too. Among the US presidential frontrunners, Donald Trump wants to build a wall along the border with Mexico, and Hillary Clinton came out against a free-trade deal whose formulation she once supported. Government approaches to the Syrian refugee crisis have been disappointingly miserly. And the UK’s future in the EU is perhaps more in doubt now that prime minister David Cameron’s efforts to hold things intact have been undermined by his tie to secret offshore investments.

Openness can be messy. If not accompanied by lucid, compassionate policies that acknowledge its downsides, it can hurt our fellow citizens, such as those who are unable to compete with cheaper labor available elsewhere.

But the benefits of more open borders are significant when you consider the reduction of poverty in countries like Vietnam and China. If managed properly, the free movement of goods should be positive even for high-wage nations, making them more efficient and richer. And research suggests that immigrants provide net benefits to the economies of those welcoming them.

We should address any dislocations that come from the lowering of borders with honesty and generosity. If we leave our children a world that is less open than it was for us, we’ll have served them poorly.

This was published as part of the Quartz Weekend Brief. Sign up for our newsletters here, tailored for morning delivery in Asia, Europe & Africa, and the Americas.