[Recently by Jon Dougherty: The Candelaria Kidnapping: Why All The Secrecy?]

Must we build a Maginot Line along the southwest border? It may take this French model of border defense to reduce the number of international incidents that occur at our border with Mexico frequently—incursions into the U.S. by armed Mexican military units.

The Bush administration seems less interested in national security than in legalizing aliens to work inside the U.S. Watching helplessly as such incursions proliferate is galling, but they are especially hard to swallow knowing so many of our sons and daughters have been sent overseas to protect the territorial integrity of other countries.[VDARE.COM NOTE: The Wall Street Journal scoffs at the idea  that the Army should defend America's borders:"[A]s if an already stretched Army doesn't have enough missions."]

A senior Border Patrol agent told me recently that they happen so often agents have been asked to use a form to report incursions to superiors.

The form incorporates the acronym "SALUTE," commonly used by military field units to report pertinent information about enemy strength:

S - size of unit (number of personnel)

A - activity

L - location and direction of travel

U - unit (identify if possible)

T - time (if reporting an earlier encounter)

E - equipment of the personnel

In other words, the level of foreign military activity along portions of the U.S. border is so frequent a special reporting system had to be adopted to keep track of them. The American Southwest isn't Iraq, Afghanistan, Bosnia, or the Korean DMZ. But it is beginning to resemble one lengthy long combat zone, especially to the agents who work it and American civilians who live there.

"The Mexican military invades our country on a regular basis," the agent says. The incursions are sometimes part of military "escape and evasion training," but sometimes merely "for protection of drug smugglers."

Obviously there is an element of danger involved for our agents, as well as for Mexican troops. The USBP agent said it was important to remember Mexican troops "are trained to escape, evade and counter-ambush if necessary" to effect their escape back across the border. He added: "Our agents have been shot at and harassed many times" by Mexican military units.

Another regular occurrence that is hard to fathom by anyone who hasn't seen it firsthand is the fact that Mexican military units and some police have also been spotted by USBP agents and American civilians funneling groups of illegal aliens northward into the United States.

"I have been out to various stations in Arizona, on detail, and have experienced contact with the Mexican military first hand," the agent says. "They actually herd groups of would-be illegal Mexican citizens up to the border and force them to cross."

Yet Washington continues to remain silent about such incursions. Indeed our current president was governor of a state which ranks second in the annual number of illegal crossings. Makes you wonder—how many Mexican military units have breached Texas soil?

The incidence of foreign military invading U.S. soil is not a partisan problem, it is an American leadership problem. Both major parties in the White House and on Capitol Hill have, for years, ignored this phenomenon. They send tens of thousands of American troops overseas to secure borders for other nations, while steadfastly refusing to allow American soldiers to protect their own country. Current law forbids the U.S. military from participating in most civil law enforcement, which is appropriate in the right context. But lawmakers supportive of open borders and unlimited immigration have been using this law as an excuse for their inaction.

Defending our borders from armed incursions by foreign military units is not "law enforcement." It's a constitutional function of government. It's a proper use of American military power—much more so, some say, than defending Europe, South Korea and Japan.

The ruling elite treats our border with Mexico as though it were an imaginary line. But the only truly illusory aspect of the U.S. Southwest border is Washington's commitment to protect it.

Jon E. Dougherty [e-mail him] is a staff reporter for NewsMax.com and author of the book, Illegals: The Imminent Threat Posed by our Unsecured U.S.-Mexico Border, published by WND Books, a division of Thomas Nelson.