For many years until quite recently, it was impossible to discuss American politics with Europeans without one of them knowingly stating that the United States was circling the drain. America was going to become a non-white country in 20 years or so, and be pillaged by proliferating Latin Americans.

The more enlightened version of this view was that pigmentation didn’t matter per se, but that the unstoppable influx of Latin Americans would turn the United States into a dysfunctional country with two languages but little bilingualism, and impossible frictions.

This is yet another illustration of the great European fantasy, which arose at the end of the Cold War. In its more ambitious form, it held that Europe would unite, and emancipate itself from the gentle overlordship of the Americans, who were no longer needed to protect Western Europe from Russia. Europe would again become the centre of the world, just as it was a hundred years ago, before it gave us two world wars, and the Communists, and the Nazis.

For good measure, the Americans would sit by like 250 million suet puddings while their country was inundated by unassimilable – and, indeed, hostile – immigrants, and simply implode as a Great Power. They had done what had proved to be their national raison d’etre: rescued the Europeans from themselves. Now the U.S. would thoughtfully remove itself in synchronization with the inexorable resurrection of a united Europe.

For 20 years, it must be said, U.S. political institutions simply ducked the issue of immigration, which was either ignored or, at best, palliated. Under successive presidents of both parties, the director of the Immigration and Naturalization Service would come on television and purposefully announce that his agency had engaged another 100 or 200 or 500 border patrol agents.

It was, of course, nonsense that the greatest military power in the history of the world, with more military strength than all other nations in the world combined, would not be able to end the porosity of its southern border. The reason for the failure was not that the United States was in a condition of terminal lassitude, as the Europeans blithely tended to imagine, or that it had a national death wish, or did not know how to control its southern border. The reason was that somebody has to do the menial work in that country, such as picking fruit and vegetables, and Americans (of any description) aren’t going to do it. There also was a general consensus that a blowtorch should be kept on the back of organized labour so American manufacturing, reduced though it has largely been to the most sophisticated skills, does not self-destruct under upward wage pressure.

It was obvious, from local political agitation in California and elsewhere, that the point was approaching whereby the consensus for toleration of illegal immigration would give way to a concern that “undocumented visitors” were overstraining the education system and social services of parts of the country. It was like turning the water on in a basin and stopping the overflow drain; the result was predictable to anyone who knew anything about the United States. It is often a generous country, but not a suicidal one.

Now, however, it is Europe that has a collapsed birthrate and is inundated with immigrants whom it cannot assimilate and who are largely antagonistic to the host countries, while the U.S. Congress has awakened from its torpor and is teeming with legislative initiatives on immigration.

The bills now visible range from the House of Representatives’ draconian measure that would build a double security fence, a virtual Maginot Line or Great Wall of China along the Mexican border, and declare illegal presence in the country to be a felony, and expel 11-million people; to methods that would allow all of those 11-million to become citizens if they seriously try to learn English and pay their taxes.

This is a complicated subject; guest-worker programs don’t work because the guests don’t leave, and illegal immigrants should not be favoured over those who have patiently followed the normal immigration rules. But 82% of Americans, a total that clearly includes an overwhelming majority of native-born Americans of all complexions, demands that the illegal entries stop.

Some compromise will be arrived at for those in the country now – “earned citizenship” it is called. It doesn’t matter what colour (or, within reason, what religion) people are, but if the United States cannot assimilate its entire population to the point of espousing loyalty to the Constitution and acceptance of English as the single official national language, the country would start to disintegrate. The people have clearly sent this message, and the Congress and the White House have received it.

Europe has a greater problem. Pope Benedict XVI has pointed out that civilizations that do not reproduce themselves die. The feebleness of Eurosocialism and the exaggerated hopes invested in Eurofederalism are relatively easy to cure. But when these great and ancient nations are so dyspeptic that their societal virility collapses, the problem is more serious than mere politics.

Lord Black is the author, most recently, of “Franklin Delano Roosevelt: Champion of Freedom.” This column originally appeared in National Post of Canada.