In a report from the Army’s Command and Staff College detailing a tactical success during the French Counterinsurgency in Algeria, we learn the following:

In the spring of 1957, the French began construction of an elaborate barrier–the Morice Line–along 200 miles of the frontier with Tunisia. Anchored by the Mediterranean Sea in the north and the Sahara Desert in the south, it was a miracle of modern technology. Its main feature was an eight foot high electric fence through which a charge of 5,000 volts was passed. There was a 45 meter minefield on either side of it, and on the Algerian side there was a barbed wire entanglement, and then a footpath, patrolled day and night. If the fence was penetrated, an alarm was automatically activated which brought instant fire from 105 mm howitzers and attack from mobile strike forces consisting of helicopters, tanks, and airborne infantry. Some 80,000 French soldiers defended the line. During the remainder of 1957 and 1958, Tunisian-based guerrillas tried every conceivable means of breaching the wire using high tension cutters, Bangalore torpedoes, tunnels, ramps, and even assaults by entire infantry battalions. French countermeasures, however, in every case proved to be decisive. By the end of 1958 the guerrillas had lost over 6,000 men and 4,300 weapons to the deadly combination of the barrier and mobile strike forces.

This accords with the intuitive conclusion of millions of American voters: Walls work.

Billions for the Pentagon, But Not a Penny for the Wall

The pyrrhic budget victory of last week included $718 billion for defense. Republicans gave everything up and allowed funding for Planned Parenthood, midnight basketball, and God knows what else, in order to keep the Department of Defense and its contractors in style. In keeping with their Reagan-era nostalgia, the congressional GOP is acting as if it were 1988, and the Cold War is in full swing. In real terms, the budget exceeds spending at the height of the Iraq Campaign, as well as the Reagan defense buildup.

What is defense? Is it not to make Americans safe from foreign attack? To prevent foreigners from imposing their way of life upon us, through invasion or other means? To maintain the independence, peace, and prosperity of the already-existing American people? Very little of what the government does in the name of defense accomplishes these things.

America maintains hundreds of overseas bases, builds and develops increasingly sophisticated conventional arms, continues to slog on inconclusively in Afghanistan, and, in spite of a smallish uniformed military, still spends mountains of money. This activity all occurs in pursuit of a broader strategy to “sustain American influence and ensure favorable balances of power that safeguard the free and open international order.” Since the focus is all on offense, perhaps we should consider going back to the old name, the Department of War.

Defense from What?

The substantial defense budget does nothing to prevent foreigners—whether mere economic migrants, violent drug gangs, or Islamic terrorists—from entering through our porous southern border. Instead, it funds bases, multiple aircraft carriers, and super-weapons to protect us from . . . who exactly? America’s death toll from the combined actions of the Russian, Chinese, and North Korean militaries over the last 20 years is exactly zero.

There, of course, have been American combat deaths in Afghanistan, Iraq, and Libya, but these occurred over a period of 17 years and were mostly perpetrated by “non-state actors.”

In spite of these expensive efforts overseas, American soldiers and civilians have continued to be killed by periodic attacks by Islamic terrorists at home, including the 55 victims of the Pulse nightclub attack, the five dead from the Chechen refugees who perpetrated the Boston Marathon bombing, the five victims of Muhammad Abdulazeez, who shot up a military base in Chattanooga Tennessee, and the 14 victims of the San Bernardino terrorist attackers, Syed Farook and Tashfeen Malik. In the case of the Boston bombing and the San Bernardino attacks, the perpetrators were not only Islamic immigrants but were permitted to enter the country after the 9/11 attacks.

Americans know they are just as in need of defense when the violence comes from a foreign-born criminal or a recently arrived Islamic extremist, as they are from the extremely remote chance that Russian (or Chinese) bombers appear overhead raining down cluster bombs on some American city. Moreover, we know that the latter scenario is almost certain not to occur while the former is unlikely to stop.

Americans, quite reasonably, expect the government to function so as to prevent these kinds of attacks, not least because a certain percentage of the defense budget is already devoted to preserving an existing nuclear arsenal. Our nuclear deterrent practically eliminates the possibility of a conventional war with a “near-peer competitor.” This permits our country to follow the counsel of George Washington, who pleaded that “our detached and distant situation invites and enables us to pursue a different course,” rather than participating in the internecine and bellicose jockeying of overseas empires.

The advantages of an ocean on either side of us, a nuclear arsenal, and a $700 billion defense budget do little good when enemies can enter through the front door and roam freely within the nation’s interior.

The 9/11 hijackers exploited our lax immigration enforcement with deadly consequence. In different ways, other foreign invaders—such as the MS-13 gang from Central America—have brought our people harm because of our unwillingness and inability to police the borders.

Liberalism Thwarts Our Most Effective Defense

Our current situation would be comic if the consequences were not so deadly. It is as if we went to war with the Empire of Japan and Nazi Germany in 1941, amassing a huge conventional force and dispatching troops to France, Okinawa, the Philippines, and North Africa, all the while letting in several hundred thousand Germans or Japanese who could make their way through the Sonoran Desert.

In fact, the situation is worse. In addition to mostly economically motivated illegal immigration from Latin America, immigrants from other, less friendly countries also try to make their way into the country through Mexico. At the same time, we are letting in a great many unvetted immigrants from hostile populations, as if their mere arrival on our shores will somehow vouchsafe their loyalty. As we saw in San Bernardino, where the foreign-born wife of Sayed Farouk joined him in his massacre, this is simply not the case.

We must be realistic; the Wall is part of a broader commitment to border security, but not the only part.

A Utopian Approach Will Kill Us

But our approach to defense is profoundly unrealistic. We invest massive sums in technology and a forward-deployed military posture, while neglecting border security and allowing in potentially deadly, unvetted immigrants from hostile countries. This lack of realism arises from two liberal impulses: technocratic utopianism and the liberal nondiscrimination principle.

The whole idea that we must invade, occupy, police, and reform Islamic lands in order to “fight them over there” and “turn them into democracies” is the utopian part. It is similar to the 1960s view that crime could only be fought with extensive anti-poverty efforts. Like the War on Poverty, our overseas War on Islamic Extremism has done little to stop the ferocity, persistence, and growth of this movement, just as urban renewal did not stop crime when criminals were given short sentences in the vain hope of rehabilitation.

What can we learn from this? Just as cops, jails, long sentences, and gated communities did much to stop the domestic crime wave of the 1970s, the most cost-effective means of addressing certain persistent problems is not to attack “root causes,” but instead to address symptoms as they appear, engage in appropriate punitive actions, and cordon off zones of safety from zones of disorder.

In his attempt to “make the world safe,” George W. Bush believed in America, but he also believed in a utopian story that everyone is, at heart, an American who wanted the American way of life.

Thus, we would “defend ourselves” by spending eight years giving the Iraqis democracy. Obama had an instinctive aversion to this kind of nation-building, because, being a more consistent liberal, he considered this all mildly imperialist. Bush and Obama both, however, denied the moral right of Americans to secure their borders by discriminating between Americans and non-Americans, even though this is an essential part of defending the actual American people.

Donald Trump’s promotion of merit-based immigration policy and “extreme vetting” for immigrants from Islamic countries affirmed a simple idea contrary to the dominant liberalism of his predecessors: Americans exist as a people, they are distinct from non-Americans, and we have a moral right to decide who gets to be in the club. That’s how the Wall became the iconic symbol of his campaign.

Trump will find his support evaporate if he does not follow through; this would go beyond a political failure, it would render the government as a whole a failure in its most basic duty to defend the American people. Unlike our many bases in Niger, Djibouti, Germany, Okinawa, South Korea, and Estonia, the Wall will actually function to protect Americans.

If France after the devastation of World War II could find the will and the funding to accomplish such a feat in one of its colonies, maybe we can spare an F-35 or two in order to do so at home.

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