Immigration is a hot-button topic these days. Some think it can even be a defining driver in future presidential elections as it certainly was in significant part in the last election, with an overwhelming majority of Latino voters supporting President Obama’s re-election.

There are many different and conflicting issues of equity, safety, fairness, and economics that surround the immigration issue, but one issue I have not heard raised (perhaps I’ve missed it) is the U.S.’s need for a larger population base among younger citizens to support the many of us who are becoming seniors as our population ages. A diminishing body of workers is carrying a larger percentage of seniors on its back than has been true for prior generations, and the situation will only worsen with time.

Our problem in this regard is nowhere near as serious as China’s where its single-child policy — strictly enforced now for more than a generation for population control reasons — means that a smaller number of younger people is, even now, helping to support a much larger older Chinese population.

This issue is addressed by historian Charles Morris in the concluding chapter of his new book, The Dawn of Innovation. The bulk of that book focuses on the fascinating story of the development of technology in America and Britain during the 19th Century and how American technological acumen (and gross domestic product) finally overtook Britain’s (the world leader by far up to that point) by the end of the century, leading America to become what he calls the “hyperpower” of the 20th Century.

His thesis is that the rise and cultivation of the middle class is what drove America’s growth and retarded Britain’s to some extent (and that of other European nations to a much greater extent). A buoyant middle class propels economic growth through its robust consumer demand and also inspires and empowers innovators to meet this consumer demand. A crucial lesson in all of this is that we need to be very concerned about what is happening now to the size and vigor of our own middle class.

It also turns out that U.S. wage rates remained higher than Britain’s throughout most of the 19th Century and further inspired innovation in the form of labor-saving technologies. Britain tended during the 19th Century to a more guild approach in production that secured people in their work in smaller scale plants even in new technologies but did not fully exploit economies of scale or encourage and inspire innovation to the same degree. (British innovation was still stellar, however, and many great technological advances up to and through the 19th Century period covered by this book were British.)

The book’s concluding chapter, “Catching Up to the Hyperpower,” focuses (interestingly but not surprisingly, given its title) on China. In that chapter, the author tries to draw — from the lessons of the 19th Century in the technological and economic race between Britain and the U.S. — lessons about how the China/U.S. race may unfold.

Both China and the U.S. face daunting challenges in technological development, pollution control and water conservation (each especially troublesome problems for China even now), and a long litany of other areas. One of those very challenging other areas the author illuminates well is the problem resulting from China’s one-child policy. He uses the term “dependency ratio” (defined as “the number of people over age 65 per 100 workers”) to help describe the problem. He then states, “By 2050, the Chinese dependency ratio will nearly quadruple.” His comparable information on the U.S. shows an almost doubling of the dependency ratio in that same time period. So while we’re not in as much of a hole on dependency ratio as China is, we still have a similar problem.

Time and again for America, immigration has been the mechanism that has solved labor shortages with hard-working and very well-motivated arrivals for whom the American dream is a shining beacon. We also have many young and hard-working immigrants in our rising generation who came here as children but were not born here (and therefore not acquiring, through their birth here, automatic U.S. citizenship). They currently exist in a limbo world of knowing no other land or culture than America’s yet being undocumented here.

Just as President Reagan did with immigration legislation in the 1980s, it’s time to regularize their status in America and also to think again about all that America has to gain, as it has in the past, from being open to bringing others within that coveted position we all enjoy of American citizenship.