Today on NPR’s “Morning Edition,” analyst Cokie Roberts understated the significance of immigration in Iowa’s 1st District, where it has become a hot issue among Republican candidates in a competitive open-seat Congressional race:

And that’s surprising, Renee, because Iowa is about 94 percent white, as opposed to the rest of the country being about 75 percent, and only 3 percent Hispanic, as opposed to the rest of the country being somewhere between 13 and 15 percent. So it’s this very white area that doesn’t really have any immigrants making immigration the focus. And this is all about, of course, getting out the Republican base in a year when that’s the only people that people expect to be voting are the base in both parties.

The Census actually tracks the number of foreign born residents in each Congressional district. And when you look at the 2002 Census, you’ll see that Iowa’s first district is about 3.5 percent foreign born and 2.2 percent foreign-born non-citizens. It’s just not true that the district “doesn’t really have any immigrants.” Those numbers may be relatively small relative to the country as a whole, which according to the Census is about 11 percent foreign born and 6.6 percent non-citizens. But if you compare Iowa’s 1st District to all the other House districts nationwide, there are more immigrants in Iowa’s district than many others — it is ranked 312 out of 435 in the number of foreign-born residents and 297 out of 435 in the number of non-citizen residents.

I also object to the implication that it’s somehow illegitimate for Republicans in the district to be concerned with immigration even though there aren’t that many immigrants there. Surely Roberts would agree that voters in Iowa should be concerned about homeland security even though they are unlikely to be the targets of a terrorist strike. Why should illegal immigration be any different?

Update 6/5 3:28 PM: A colleague pointed out that Iowa has had substantial growth in immigration due to the meatpacking plants located in the state — a fact that I was aware of but hadn’t focused on. So I calculated the increase in the number of foreign born residents as a proportion of the population in each state between the 1990 census and 2000 census. Among the 50 states, Iowa had the 10th fastest growth in the proportion of foreign born residents during that period, with the number doubling from 1.56 percent to 3.11 percent. Presumably the inflow includes a substantial number of undocumented immigrants. Why is it so “surprising” that Iowa Republicans are concerned about this issue?

To put this in perspective, here is a bar chart of the increase in the proportion of foreign born residents by state from 1990-2000 showing Iowa at #10:

Note also that there is essentially zero correlation between the total proportion of foreign born residents in 2000 and the increase in the proportion of foreign born residents between 1990 and 2000. The increased inflows are not going to states like New York and California. In fact, none of the states that experienced the greatest increases (North Carolina, Georgia, Arkansas, Nebraska, Tennessee, Kentucky, Utah, Minnesota, South Carolina and Iowa) is in the Northeast or on the West Coast. Immigration has surged in the so-called “heartland,” which is the home of much of the Republican base. It’s therefore not so “surprising” that GOP primary voters are concerned about the issue…