
[Note: This piece is too long to appear fully as an e-mail. If you got this by e-mail, please click on the title to read the entire post on Substack.]
Immigration has taken center stage in politics, with daily headlines about Congress clashing over the border and large cities struggling to handle hundreds of thousands of recent arrivals. In a new Pew poll, 78% of Americans say that the border situation is a “crisis” or “a major problem.”
In February, Gallup reported that a record-high 55% of Americans consider “large numbers of immigrants entering the United States illegally” a critical issue. The prior high, 50%, was two decades ago in 2004. Meanwhile, 28% say that immigration is the most important problem facing the country: the highest share since Gallup began tracking sentiment about immigration in 1981.
To quantify the scale of the migrant crisis, news outlets typically highlight the record numbers of people who have been apprehended at the southern border over the past year. Yet while this figure sheds light on what’s going on at the border, it does not address the larger question of what’s going on with net immigration overall.
For example, how many immigrants are entering and leaving the country? How have these figures changed over time? How many total immigrants are in the United States? And is their share of the total population growing or declining?
How immigration is measured
All right. So how do we answer these questions? The obvious answer would be to count everyone coming into and out of the United States who are not commuters, tourists, or business visitors.
The thing is, nobody can possibly do this. It is vastly beyond the abilities of any person or agency. Immigrants enter through so many different routes—legal, extralegal, and often clandestine—that government agencies reporting official numbers have a difficult time keeping track even of legal immigration flows. Making things exponentially harder is the fact that the net flow is the difference between two sizeable streams moving in opposite directions: Many people enter the United States when living here seems like it would be better than living in their countries of origin and then return to their countries of origin when the reverse is true.