In Jean Raspail's 1973 dystopian novel, "The Camp of the Saints," about 1 million poor folks from India make their way on hundreds of ships around the southern tip of Africa and up to the French Riviera. The international media use helicopters to follow the flotilla, and the news of the flotilla's movements dominates the headlines for weeks.

As the flotilla gets closer to France, panic sets in, and fear becomes a political weapon. The government doesn't know what to do. The president of France finally orders the French military to secure the borders and use deadly force to prevent the flotilla from landing.

Then, after pangs of conscience set in and animate him, the president tells senior military personnel to instruct their troops to use their own judgment and do the right thing. With the exception of some stereotypical holdouts, the military members take their arms and flee into the countryside.

The flotilla lands. The passengers have no desire to assimilate, and they murder people who do not welcome them. They change immigration laws and become a paradigm for other mass migrations. Across the West, pro-immigrant governments are established.

When the book was first published, it found favor in many nativist quarters. It is brilliantly written, and the standard English translation offers compelling reading and is hard to put down. It is also rabidly racist, portraying nearly all in the West as thoughtful, intelligent and honest and nearly everyone of color as avaricious, lazy and amoral.

Regrettably, the book has been seen in the West Wing of the White House.

I recount this brief summary of a French literary work because I fear its unrealistic ending and harsh, racist treatment of those seeking a better world may be animating Trump administration policies about the caravan of 7,000 folks from Latin America who are in Mexico and walking toward the United States.

Like the fictional French president, President Donald Trump has made unsubstantiated allegations that bad people are in the midst of the caravan. And like the fictional French president before his change of heart, Trump has called himself a nationalist.

Nationalism and its cousin nativism are dangerous attitudes that have come and gone almost cyclically throughout American history. They foster an arrogant aura about Americans who embrace them — we are more deserving than you because our ancestors got here before you or yours did — and they cause fear and hatred of foreign-born people.

They also lull one into the lazy mental habit of judging the moral worth of people not on the basis of their personal choices and fidelity to first principles but on the basis of their membership in groups marked by immutable characteristics of birth, such as people's place of birth.

This habit rejects a founding American principle that we are all created equal and endowed by our "Creator with certain unalienable Rights, that among these are Life, Liberty, and the Pursuit of Happiness."

The quoted words above are not just Thomas Jefferson's most famous musings, which made their way into the Declaration of Independence; rather, they embody natural law. And natural law teaches that human rights come from our humanity — not from the government — and they adhere in everyone, not just Americans.

I have argued in this column that the right to travel is a natural right, even though it was not until 1969 that the Supreme Court recognized it as such. The courts protect natural rights by imposing a very high bar for the government to meet before it can interfere with them. That bar — called strict scrutiny — was crafted so as to make it nearly impossible for the government to interfere materially with personal freedoms, such as travel.

And the Constitution itself, from which all federal powers derive, does not even delegate to the federal government any power over immigration — i.e., who can come here. It just gives it power over naturalization, i.e., who can become a citizen here.

The likely claim of the folks in the caravan will be political asylum. Political asylum requires the claimant to demonstrate an intolerable situation in the home country caused by the government — not by economic forces — and aimed at the person seeking asylum. Thus, the failure of the government in the country of origin to protect basic natural rights or to enforce basic criminal laws — for example, permitting criminal gangs to rule — is a valid basis for asylum, whereas loss of a job is not.

Once an asylum-seeker has so much as the tip of her shoe on American soil, she can file an asylum claim. The claim entitles her to a hearing before an immigration judge. Most of these hearings take six to eight months after the claim has been filed to reach a judge. In the Obama years, asylum claimants were set free until their hearings. The Trump administration has detained them and separated children from their parents. The detentions are lawful; the family separations are not.

Yet people who want to work should be allowed in. My colleagues at The Wall Street Journal have demonstrated indisputably that most of the work that immigrants will do is work most Americans eschew. Their work not only benefits them but also produces family stability and increases wealth, which finds its way into the stream of commerce.

The blanket rejection by force of everyone in the caravan violates the spirit and the intentions of the laws the president has sworn to uphold. Those laws mandate a careful examination of all who want to come here — on a neutral case-by-case basis — not a blanket prohibition.

We who call ourselves Americans are nearly all descended from immigrants. Yet when our forebears arrived here, they were met simply by prejudice and government indifference. The poor folks in the caravan are likely to be met by prejudice and government force.