On the front of Time magazine is a now famous picture of a little girl crying, superimposed on a red background with President Trump looking down at her. The headline: “Welcome to America.”

Trump wasn’t there when her photo was taken of course: she and her mother, an illegal immigrant, were picked up on the Texas border on June 12^th and placed in custody. Time initially reported that they were separated as per Trump administration policy. They were not (the mother was told briefly to put down the child in order to be searched). Regardless of Time’s correction, the image remains that of an exhausted, possibly terrified little girl: the face of a migrant crisis that, for many, reflects the iniquities of capitalism and the inhumanity of America’s immigration policy.

There is is more to that tale, however. The father of the girl says the family is from Honduras and that she has three other siblings. According to him, the mother left with the child without telling anyone, and perhaps paid a people-smuggler around $6,000. This was the second time the woman had tried to reach the United States. “I don’t have any resentment for my wife,” said the husband, “but I do think it was irresponsible of her to take the baby with her in her arms because we don’t know what could happen.”

Irresponsible or desperate? Criminal or legitimate? Economic migrant or refugee? One can be all of those things with scant contradiction. A desperate person often acts irresponsibly; anyone who breaks the law to help their children is forgivable; the line between escaping oppression and poverty is very thin.

And the image of a distraught child is sufficient narrative in itself because it tells you there’s something very wrong here and change is needed. But what, precisely? Are we Catholics ready to confront the moral complexities of the biggest challenge facing our generation?

Put aside whatever you think or feel about immigration and it comes down to this: the world is on the move in numbers never seen before, and not necessarily for the traditional reasons of famine or war.

Those things have a lot to do with it, sure. Honduras, for instance, is genuinely horrible, characterized by poverty, crime, corruption and a high murder rate. But in many cases, people are moving because the absolute poverty rate has lifted slightly and they can afford to do it. Mobile phones and the internet make migration easier; profitable networks of smuggling have sprung out of deserts and across oceans.

What is a rich Western country to do? The obvious Christian answer is “let everyone in”, but it’s not as easy as it sounds. Democratic statesmen are elected not to embody Christ but to represent voters, and the weight of public opinion leans towards the demand for control. This might not be saintly, but it is rational and reasonable. Immigration has a demonstrable effect on wages, crime and cultural identity. It is neither mad nor fascist to observe that if a group of people arrive in a country on a vast scale, they are likely to change its character.

The response, including by moderate politicians, can be panicked and tragic. It is believed, for instance, that child separation may have occurred under Obama. Mr. Liberal in fact holds the record for official deportations: 435,498 in 2013. Obama embraced the privately run family detention centers. Obama applied extreme vetting of migrants from select countries. Obama ended a policy that let Cuban refugees enter America without visas. And how much did Obama contribute to conflicts that caused people to move?

During the controversy over separation, I was intrigued to see Samantha Power attacking Trump on Twitter. Ms. Power was one of the influencers behind the West’s intervention in Libya, which has helped to destroy that nation and drive thousands across the Mediterranean.

Ultimately, whether one bombs children, separates them from their families or finds oneself watching them drown, it all amounts to a confused picture of the West causing misery whatever it tries to do.

The lesson from Australia seems to be that a crackdown on illegal immigration reduces proximate disaster because it deters people from putting their lives at risk. It does not, of course, alleviate the misery that would cause them to take that risk in the first place.

In short, I see no satisfactory answer to the great migration, only a prophecy of crisis. If we Westerners want our world to remain as comfortable and liberal as it is, we may well need to guard it – but at the cost of the very Christian spirit that makes it the kind of place people want to run to. I despair of Trump and his methods, but he has identified and exploited an inescapable dilemma.