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The Border Patrol apprehended 2,060 aliens from the People's Republic of China crossing the U.S.-Mexico border in fiscal year 2019, according to U.S. Customs and Border Protection.

The Border Patrol defines an "apprehension" as "the physical control or temporary detainment of a person who is not lawfully in the U.S. which may or may not result in an arrest."

A Border Patrol datasheet lists the number of "total apprehensions" it made in fiscal year 2019 by both the citizenship of those apprehended and the border sector where the apprehension took place.

In fiscal year 2019, the Border Patrol apprehended a total of 2,134 Chinese nationals. This included the 2,060 apprehended at the Mexican border, 47 at the Canadian border and 27 at coastal borders, which include the Border Patrol's New Orleans Sector, Miami Sector and Ramey Sector in Puerto Rico.

Clearly, people from China seeking to become "not lawfully" present in the United States are more likely to come here through Mexico than through Canada or by sea.

But this is not only true for aspiring illegal immigrants from the People's Republic.

It is also true, for example, for people from Iran, Afghanistan, Iraq and Syria.

In fiscal 2019, the Border Patrol apprehended 24 Iranians, including 14 at the Mexican border, 8 at the Canadian border and 2 at the coastal borders.

It apprehended 17 Afghanis, including 12 at the Mexican border and five at the Canadian border.

It apprehended six Iraqis, including four at the Mexican border and two at the Canadian border.

It apprehended three Syrians, including two at the Mexican border and one at the Canadian border.

This is not a new phenomenon.

The Border Patrol datasheet also includes the number of "deportable aliens" it apprehended in fiscal 2007 through 2018. These are also listed by nationality and by the border sector where the apprehension occurred.

From fiscal 2007 through 2018, the largest number of "deportable" Chinese nationals the Border Patrol apprehended was in fiscal 2016. That year, it apprehended a total of 2,439 "deportable" Chinese nationals. Of these, 2,320 were apprehended at the Mexican border, 52 at the Canadian border and 67 at the coastal borders.

In each of the last four years, according to a Border Patrol data sheet on "illegal alien apprehensions," the Border Patrol has apprehended more people crossing the Mexican border who were not from Mexico than who were from Mexico.

Of the 851,508 illegal aliens the Border Patrol apprehended along the U.S.-Mexico border in fiscal 2019, 166,458 were from Mexico, but 685,050 were from countries other than Mexico.

In other words, 80.5% of the "illegal aliens" the Border Patrol apprehended at the Mexican border came from some other country and tried to use the U.S.-Mexico border as a pathway into the United States.

This percentage has escalated over the past four fiscal years. In fiscal 2016, 218,110 of the 408,870 "illegal aliens" apprehended at the Mexican border -- or 53.3% -- were from countries other than Mexico.

In fiscal 2017, it was 175,978 of 303,916 -- or 57.9%.

In fiscal 2018, it was 244,322 of 396,579 -- or 61.6%.

By far, the largest numbers in fiscal 2019 came from Guatemala (264,168) and Honduras (253,795). But, as noted, the same path for possible illegal entry also appealed to aspiring border crossers from as far away as Iraq, Iran, Afghanistan and Syria.

At a time when Americans in some communities are being told to shelter in their homes to protect themselves from a virus, aliens from all over the world are still coming to our southern border hoping to cross illegally into the United States.

If they qualify for asylum because they have a well-founded fear of persecution at home, they should get asylum.

But not so long ago, some interesting Washington establishmentarians saw the flow of other-than-Mexicans to our southern border as a national security problem.

On Feb. 16, 2005, retired Adm. James Loy, then deputy secretary of Homeland Security, testified in the Senate Select Committee on Intelligence.

"Recent information from ongoing investigation, detentions, and emerging threat streams strongly suggests that al-Qaida has considered using the Southwest Border to infiltrate the United States," Loy said in his written statement to the committee.

"Several al-Qaida leaders believe illegal entry is more advantageous than legal entry for operational security reasons," he said.

"However, there is currently no conclusive evidence that indicates al-Qaida operatives have made successful penetrations into the United States via this method," he said.

Democratic Sen. Diane Feinstein of California took careful notice of this testimony.

"I view a worldwide threat to be our borders," she said during that 2005 hearing.

She then quoted Loy's written statement back to him.

"I think that is a very important statement, particularly when you consider the fact that a half-a-million other-than-Mexican intrusions have been made on our borders since 2000," she said.

"Now, I've looked at the statistics for each country," Feinstein said. "And the so-called countries of concern -- Syria, Iran, others -- the numbers are up of penetrations through our southwest border."

In 2007, the Border Patrol apprehended 3 deportable aliens from Syria at the Mexican border and 12 from Iran.

Have Feinstein and her colleagues fixed the problem?