WASHINGTON — Until the advent of Donald Trump's presidential candidacy, the word "immigration" tended to mean the controlled and more-or-less legal movement of one people to another country. Oh, there were always "border troubles" here and there, but nothing to (so to speak) write home about.

Today, immigration has become a weapon of foreign policy on the part of certain states; it has become the No. 1 question, and the most irritating one, in the campaign for the presidency; and it has incorporated the intention of some failed states and brutal terrorist groups to destroy Western democracies — from within.

Since these questions — of where people belong, what citizenship really entails, and how important cultural identity is to human beings — are now of utmost importance to nations like the United States and the members of the European Union, let us consider some of them, one by one.

• Why are so many Syrians trying to emigrate, especially to Europe?

Well, of course, they are trying to escape the terrible killing fields, but few observers have noted another salient reason for the emigration outward: Syria's extraordinary population growth.

Anthony H. Cordesman, a brilliant political analyst at the Center for Strategic and International Studies, wrote recently in a paper on Syria that the U.S. Census Bureau estimates that Syria's population has grown from 3.5 million in 1950 to 22.9 million in 2015.

"They never created enough jobs or promises of a meaningful future for one of the youngest populations in the world — one where the CIA estimates that 32.5 percent are 14 years of age or younger, and 19.9 percent are in the age group from 15 to 24," Cordesman wrote. "The GDP was only some $5,200 in 2010, ranking only 165th in the world."

So, you're telling me that this kind of raw, unchecked population surge is in great part to blame? Yes, I am.

• Why should America, which already accepts more refugees than any other country in the world, now accept tens of thousands of Syrians?

A former Obama adviser being interviewed on CNN recently pointed out that it had been good to bring many Iraqis here after the Iraq war, particularly those who had helped us over there, because they would suffer at home. Then he added brightly, "Now, if we get into trouble around the world, it shows how we can bring the people who help us here."

Excuse me, but I thought the idea was to NOT get into "trouble" again.

• Another of the arguments put forward for bringing more immigrants here is that it is not the first generation that joins terrorist gangs, but the second. Thus, why not let them come?

Perhaps I've misunderstood again, but that is a self-contradicting statement. It says that we can welcome these immigrants into our land and society and then expect the worst.

• What were the five Syrians thinking when they were caught presenting fake passports in Honduras last week?

I'll bet they didn't know that poor little Honduras has the highest murder rate in the world and that they'd be lucky indeed to get out with their own lives. But, let's hand it to the Hondurans. Muchas gracias, senores amigos!

• One of the major arguments for allowing more immigrants into the U.S. has involved minors who've been separated from their parents or sent alone. How can children hurt you?

As it happens, last Sunday The Washington Post ran a fascinating article about how a 17-year-old from Sterling, a 22-year-old from Montgomery Village and a 22-year-old from Herndon (all suburban Washington areas) had been killed this year. Two were shot; one was butchered with knives and a machete.

After you read way, way down into the story, you discover that the alleged killers entered the country during the recent waves of "unaccompanied minors" crossing the Texas border. Apparently they had ties to the brutal MS-13 Salvadoran gang that police have been trying desperately to wipe out for years.

Iowa Republican Sen. Charles E. Grassley wrote to security officials: "This tragedy appears to be yet another example of problems in the vetting of unaccompanied minors. In this case, minors with possible gang ties were allowed to go off the grid after entering the country illegally."

And you still think immigrants— big, little or medium-sized — don't pose any danger? You still think they don't carry their own cultural values and threats with them, as indeed we all do? Well, keep tuning in, and we'll see how many more absurdities we can skewer in this crucially important debate.

Georgie Anne Geyer has been a foreign correspondent and commentator on international affairs for more than 40 years. She can be reached at gigi_geyer(at)juno.com.

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