"The United States shall guarantee to every State in this Union a Republican Form of Government, and shall protect each of them against Invasion."
So reads Article IV, Section 4 of the Constitution.
Historically, that constitutional duty — to protect America's states against invasion — has been the province of the president of the United States, the chief executive, who today is Joe Biden.
How did Biden's predecessors do in discharging their duty to secure America's borders?
During the War of 1812, President James Madison assigned the defense of New Orleans against an invading British army that had just burned the Capitol and White House to Gen. Andrew Jackson.
On Jan. 8, 1815, Jackson crushed the battle-hardened and numerically superior British force that had invaded our country.
Jackson was also the chosen instrument of President James Monroe to punish and expel Indian marauders raiding Georgia from Spanish Florida in 1818.
Exceeding his mandate, the resolute Jackson entered Florida, expelled the Spanish governor, and annexed the peninsula for the United States after executing two British subjects and almost igniting a war with Great Britain.
In 1845, President James K. Polk sent an American army to Texas to validate our claim to all the land north of the Rio Grande that had belonged to the Lone Star Republic when it seceded from Mexico in 1836 and joined the Union in December of 1845.
President Andrew Johnson sent an army to the Mexican border to effect the removal of a French army and Paris-backed regime that had colonized Mexico while the Union was preoccupied with the Confederacy.
The French departed, leaving behind the hapless Habsburg emperor they had installed to face a firing squad.
When Pancho Villa conducted his murderous raid into Columbus, New Mexico, in 1916, Woodrow Wilson sent Gen. John Pershing with an army of 6,000 into Mexico to run him down. They never caught Villa.
By Dwight Eisenhower's first term, 1 million illegal immigrants had moved into the United States from Mexico. Ike commissioned his friend and West Point classmate Gen. Joseph Swing to effect their removal.
All of these incidents involved America's southern border, and each of the presidents of that day took seriously their constitutional duty to defend the nation's borders against invasion, violent or nonviolent.
And how has President Joe Biden discharged that obligation?
In Biden's first year as president, some 1.7 million Illegal migrants were intercepted crossing into the United States.
The monthly figure from Fiscal Year 2021 was exceeded by the March 2022 figure of 220,000 migrants crossing over into the USA. If sustained, this rate would translate into an invasion of 2.6 million people, predominantly young and predominantly male, in the 2022 fiscal year alone.
"Gotaways," those who breach our borders without ever being stopped and identified by Border Patrol or other authorities, are now estimated at 30,000 a month. Among these clandestinely crossing our border monthly are cartel members, child molesters, drug traffickers, and sex offenders. We don't know who they are, but we do know where they are. They are now our neighbors inside our homeland.
Biden is now planning in May to lift Title 42, which requires that unvaccinated migrants seeking entry at the border remain in Mexico.
According to ABC, the Department of Homeland Security is bracing for as many as 18,000 migrants per day at the U.S. southern border if Title 42 is revoked.
Most of these migrants still come from Mexico, Guatemala, Honduras, and El Salvador, but growing numbers now come from all over the world. They are of every race, nationality, culture, creed, and ethnicity, and they are steadily converting America from a First World Western nation into a predominantly Third World country.
By failing or refusing to do his constitutional duty to defend the nation from invasion, Biden is letting this happen. Through his passivity and inaction, he is remaking America. What we are witnessing is the Third Worldization of the USA.
What do these endless thousands of migrants at the southern gates of our country bring with them? A desire for a better life, surely, but also a vast dependency on a deeply indebted America for social welfare, housing, health care, and education.
Most come with little in the way of skills and almost nothing in the way of personal wealth or a knowledge of our history, heritage, and language.
Their first act on the road to residency and eventual citizenship in this country is to break the laws of the United States by first breaking into our country.
A move is afoot to impeach Biden for his failure to do his constitutional duty and defend the southern border of the United States from the invading millions of illegal migrants.
But that would make impeachment the subject of national debate, not the massive illegal migration and the changes it is producing in the character of our country.
Indeed, who stands first in line to succeed an impeached and convicted Joe Biden? Kamala Harris, Biden's designee to act as America's "border czar."
Pat Buchanan has been a senior adviser to three presidents, twice a candidate for the Republican presidential nomination and the presidential nominee of the Reform Party in 2000. Buchanan has written eight books, including four New York Times best-sellers. He is married to the former Shelley Ann Scarney, a member of the White House staff from 1969 to 1975.