Over the past few years, confusion has developed among some in the conservative movement who have allowed a legitimate concern over border security to become conflated with anti-immigration politics. As this confusion threatens to saddle the Republican Party with a platform that would be both detrimental to the nation and catastrophic to conservatism’s political prospects, it is imperative, at this point, that we step back and consider, on the basis of first principles, what a proper immigration policy should be.

It should be clear that the bedrock foundation of any rational immigration policy should be to seek the benefit of America, rather than that of potential or existing immigrants, or any other particular group either supportive or antagonistic to them. That said, let us consider the effect of immigration upon our economic well-being.

In any economy, the entire population is supported by the part of it that is of working age. Therefore, it behooves any society to seek to maximize the ratio of working-age citizens to the total. Other things being equal, it follows that the most attractive acquisition a society can make is a young adult, whose childhood and education have already been paid for, but whose entire working life still lies ahead. Of course, all other things are not equal. Those with more skills are greater prizes, as they cost more to create and are likely to be more productive in life. This being the case, it is absurd to deny young foreigners who graduate American universities a path to citizenship.

This logic remains valid, albeit with less clarity, for young adults of a lesser eminence but still, on-net, above-average prospects, including but not limited to those in the military or college-accepted high school graduates who would be enfranchised by the DREAM act.

This being the fundamental economic reality, the primary counter argument that has been mustered against it has been that of labor protectionism. Thus, for example, in a recent PJ Media article attacking Mitt Romney’s proposal to guarantee a green card to every foreigner who earns a science, technology, engineering, or math (STEM) degree in the United States, Jessica Vaughan, the director of policy studies at the Center for Immigration Studies, writes:

As for stapling the green card to the STEM diploma, this is little more than a marketing tool for U.S. universities to attract more foreign students into paying for degrees in fields that are already saturated. There is no shortage of STEM professionals in the United States; on the contrary, the census shows that there are 1.8 million American engineers who are unemployed or working in other professions.

Setting aside criticism of its questionable statistic (the total number of U.S. unemployed is 13 million), the illogic of this argument is astonishing. Where, pray tell, does Ms. Vaughan imagine that jobs come from? Are they a fixed resource with only so many to go around? Then, is it the case that there were 150 million jobs available here when the pilgrims landed and they have now been filled up? Are the present high American unemployment rates actually being caused by overpopulation? If so, why then were unemployment rates three times as high in 1932, when the U.S. workforce was 1/3 its present size?

No, jobs are not a resource that exists separately from people, jobs are created by people. Immigrants are notoriously entrepreneurial, and the statistics back up the stereotype. While immigrants comprise 13 percent of the American population, they own 18 percent of small businesses and, according a recent study by the Fiscal Policy Institute, were responsible for 30 percent of the growth of U.S. small businesses over the past two decades.

So immigrants as a whole are net job creators. But of all immigrants, STEM graduates are by far the most promising because their advanced training allows them to create not only small businesses, but large ones, including such recent examples as Intel, SpaceX, Google, eBay, Nvidia, and Yahoo. The nation is indeed suffering from a shortage of such people.

Furthermore, the idea that by excluding immigrant talent from the U.S. workforce we can prevent it from competing with Americans is risible. Rather, by excluding skilled or educated foreigners, we guarantee that they will compete with American workers and businesses from their home countries, which will pay them less or allow them to hire local labor at lower than U.S. pay scales. As a result, the jobs, industrial capabilities, and tax revenue that they could have created here will be created over there instead, while America’s position in the world market will be further eroded. To cap it all, by giving up the effort to compete for such talent without a fight, we effectively build a Berlin Wall for the benefit of our foreign competition, allowing them to retain skilled people without making the concessions to both liberty and living standards that would otherwise be forced upon them.

Vaughan objects to American universities financing themselves by charging out-of-state tuition to foreign students. But what’s not to like? Foreign students that come to the U.S. and pay triple the tuition of their American counterparts provide a major subsidy to our educational system. Each such person effectively pays not only for his own college education, but that of two Americans as well. If we were to add the incentive of a green card to the degree, the numbers of such people would expand considerably and make university education much more affordable for Americans.

And education is not the only area where Americans could reap enormous savings by rejecting the arguments of the labor protectionists. Another is health care. Because of the limited numbers of American medical school graduates, many specialist doctors are currently taking home salaries above $400,000 per year. That may be nice for them, but it imposes excessive medical care costs on everyone else, and because these costs are typically passed on via health insurance to employers, it is making American industry less competitive internationally, and thereby contributing to unemployment.

Furthermore, because such specialist salaries are so high, they are having the effect of depleting the number of doctors involved in primary care, and thereby stripping parts of the nation — whether covered with insurance or not — of their access to timely medical assistance. These problems could be readily solved by opening our doors to foreign medical talent.

It is odd that the anti-immigrant’s labor-protectionist argument has been allowed to pass with so little challenge, as it obviously contradicts every well-proven principle of free-enterprise economics. Nor do immigration-restriction politics have a valid basis in any other legitimate source of American conservative philosophy. Quite the contrary, since the first Thanksgiving, America’s tradition has been to welcome immigrants, and it was only with the advent of the progressive movement in the early twentieth century that a significant faction of educated opinion aligned itself otherwise.

Embracing eugenics, environmentalism, and Malthusian ideology and suffering from delusions of grandeur as the would-be elite managers of all aspects of society, the progressives sought to institute immigration restriction as a way of controlling and culling the eugenic qualities of what they saw as the nation’s herd of human racial “stock.” Using IQ tests (delivered in English and containing many questions relating to baseball or other aspects of Americana) of World War I army recruits as pseudo-scientific proof of the mental inferiority of immigrants, the progressives pushed through laws in the 1920s sharply restricting the immigration of Jews, Slavs, Italians, and other Southern and Eastern Europeans into the United States.

The same crowd created environmentalism as a political movement in order to restrict access to America’s natural resources. They also created the federal bureaucracy as a way of restricting Americans’ personal liberty. Thus, if you go to the redwood forest in California today, you will encounter a plaque to the three leaders of the Save the Redwoods League, Madison Grant, Henry Fairfield Osborn, and Charles Merriam. All three were eugenicists and personal associates of Theodore Roosevelt, progressivism’s founding father. Grant was also vice president of the Immigration Restriction League and the author of the Aryan-supremacist classic, The Passing of the Great Race.

Osborn was the vice president of the American Eugenics Society and president of the American Museum of Natural History. In his remarkable keynote speech to the Third International Congress on Eugenics held at the museum in 1932, Osborn drew the connection between environmentalism, immigration restriction, and eugenics clearly by stating that overpopulation by allegedly inferior people (including in the United States, with a population of 125 million) was causing resource destruction and unemployment. Two years later, Osborn received the Goethe Medal from Adolf Hitler, but then died, leaving his part in the cause to be carried on by his son, Fairfield Osborn, who kicked off the postwar environmentalist movement with his 1948 bestseller Our Plundered Planet, and his nephew, American Eugenics Society president Frederick Osborn, who, together with John D. Rockefeller III, founded the population control movement flagship Population Council in 1952. It is from this rotten tree that the anti-immigration movement has sprung.

A rotten tree cannot bear good fruit.

America is not a race state. It is a country defined by a set of ideas, and when people choose to accept those ideas they become Americans, as fully so as any — and perhaps more so than most — regardless of how recently they or their ancestors arrived upon our shores. If you peruse the roll call of the nation’s leaders in science, engineering, medicine, industry, business, literature, soldiering, and politics (including, most definitely, conservative journalism), you will see many names whose presence on these shores the eugenicists would have precluded if they could. Yet they are here, along with myriads of others of their many kinds, and this nation would not be remotely as vibrant, inventive, prosperous, or powerful without them.

This is the true American tradition, which, as conservatives, we must defend, regardless of the antics of demagogues who seek to drive us down another course. Societies become decadent when they abandon their formative principle. We should not abandon ours, which is inclusion and growth, not exclusion and stasis. Americans are not weaklings who need to cower behind an exclusionary curtain, shivering in fear that if too many join us there might not be enough sinecures to go around. Rather, our continuing custom should be to bravely welcome new talent into our ranks, sure in our knowledge, and in our faith, that the more of us there are, the more opportunities we can create, and the more great things we can do.

Americans comprise 4 percent of the world’s population, yet are responsible for half its inventions. Consequently the world needs more Americans, and so do we.