Immigration reform is shaping up to be the next big thing in domestic policy, so maybe it wasn't such a surprise that I found myself thinking about the issue the other night as I watched a PBS documentary about Mount Rushmore.

That's right, Mount Rushmore. Sure, none of the four presidents on the mountain was an immigrant, but three of the four – all but George Washington – dealt with immigration issues as president, which tells you something about the persistence of immigration, and anti-immigration, as a theme in American politics.

Thomas Jefferson received enthusiastic support from Irish Protestants like Thomas Addis Emmet and others who sailed to America after the failed rebellion of 1798. Federalists openly condemned nefarious "foreign influences" in New York, adopted home of Emmet and other United Irish exiles.

Lincoln, of course, depended on the patriotism and courage of immigrants and first-generation Irish Americans as he undertook a crusade to preserve the Union and, in the end, to abolish slavery.

The New York of Teddy Roosevelt's youth and young adulthood was a Babel of languages and customs. He lived within easy walking distance of the Lower East Side, that chaotic, tumultuous urban mosaic where Irish and Jews and Italians, among others, shared sidewalks, streets and a good deal more.

Roosevelt, in later life, came to the conclusion that native stock white Anglo Saxon Protestants were committing what he called "race suicide" because immigrant birth rates were so much higher than those of said native stock.

These connections, between Mount Rushmore and immigration through the lives of three presidents, may be of some interest but they're not why I found myself pondering immigration reform as I watched the documentary.

It was, ironically enough, a story about a Native American park ranger at Mount Rushmore and the stories he told which led me to consider some of the questions raised about today's immigrants, particularly concerns that today's immigrants cannot (or will not) be assimilated into American culture.

Gerard Baker is the first Native American supervisor of Mount Rushmore National Park. His people, the Mandan-Hidatsa, lived in the Dakotas long before the first Europeans landed on these shores.

When George Custer arrived and gold was discovered in those hills after the Civil War, the life of the Plains Indians changed dramatically, and not for the better.

The wounds of more than a century ago still have not healed. One member of the Lakota tribe talked about how white people profaned the tribe's sacred ground in the Black Hills.

Just when a viewer might have expected to hear a litany of the crimes committed within viewing distance of Mount Rushmore, Baker began to speak about the values symbolized by the four presidents memorialized on the mountain, of the importance of freedom and liberty, of the power of democracy.

His remarks, his homage to the country's ideals, sounded very mainstream, very patriotic, and very American. It was easy to forget that the speaker was the descendant of men and women who were nearly wiped out in the mad rush for gold, land, and other riches in the American heartland more than a century ago.

Baker is trying to expand our knowledge of ourselves and our country by including Native American culture in programs at Mount Rushmore. Some, apparently, have taken offense, but Baker persists, just as Irish Americans insisted on marching up Fifth Avenue every March 17, demanding that New York pay attention.

What does this have to do with immigration? Just about everything, for Americans in the late 19th Century and early 20th Century would have argued that the likes of Superintendent Baker could not possibly become informed citizens of the great American republic.

That's why they were herded off to reservations, where they could practice their strange customs on their own land, far away from irresistible forces that would bring progress and prosperity to the primitive landscape of the Plains and the Southwest.

Native Americans and Catholics and Jews and African Americans were all deemed threats to American liberties and ideology at one point or another over the last two centuries. Today, immigrants from Mexico and other places are portrayed in the same way. They refuse to speak English, it is said. They are criminals; they are lazy; they use up precious resources but contribute nothing to the common good. They refuse to become, in a word, American.

Of course, immigrants have always redefined what the word "American" means, none more so than the Irish Catholics who showed that it was possible to be American without being Protestant, a huge but historically forgotten challenge to the nation's self-image.

Today's immigrants, from the Southwest Asians behind our motel lobbies to Mexicans trimming our suburban lawns, are bound to redefine our ideas of being American in the 21st Century.

That's the historic point missing in today's debate over immigration reform, a point that was brought home to me through the words of a true Native American – as opposed to the Native Americans whose low birth rates so worried Teddy Roosevelt.

That said, however, immigrant advocates would be well-advised to acknowledge that border security in the era of global terrorism is a legitimate concern.

Only pro-immigration extremists – and there are a few of them out there – would argue otherwise. Any immigration reform must be accompanied by stricter border control, particularly in the South West.

Pro-immigrant groups will get nowhere if they remain blind to the legitimate anxiety of Americans who fear that porous borders are an invitation to further attacks. Yes, the most recent threats have been home-grown, but that is a sign that tighter controls are working.

It is, in fact, possible to speak up for immigrants while also acknowledging security concerns. That simple acknowledgment could move the debate along at a time when clearly something has to be done.