The 1965 Immigration and Nationality Act replaced the restrictionist and explicitly racist Immigration Act of 1924. In 1965 there were 6.9 million foreign-born persons in the United State. Today there about 45 million.

Between 1965 and 2015, new immigrants, their children and their grandchildren accounted for 55% of U.S. population growth. They added 72 million people to the nation’s population as it grew from 193 million in 1965 to 324 million in 2015. Growth of this size was not anticipated in 1965.

In 1980, foreign-born persons were geographically concentrated pretty much as they were in the 1920s – in California, the Northeastern cities, and some old cities in the interior such as Chicago. Since about 1980 they have spread throughout the country.

The combined population share of immigrants and their U.S.-born children was 26% in 2015 and has also certainly risen. That percentage (which leaves out third generation) is projected to rise to 36% in 2065, at least equaling previous peak levels at the turn of the 20th century.

From Pew Research.

The Migration Policy Institute is one of the best sources of information about immigration in the United States. Julius Hattem, editor of MPI’s newsletter, wrote on October 16 about caravans from Central America. I have included below his commentary in full.

Two years ago this week, about 160 people set off from San Pedro Sula, Honduras, headed towards Mexico and, for many, eventually the United States. In following weeks their numbers would swell to form a caravan of about 7,000 people that moved into Guatemala and across the Mexican border, traveling in a group for safety and as a political signal. In the United States, the migrants became a rallying cry for President Donald Trump ahead of midterm elections that would see his Republican Party expand its Senate majority.

In recent weeks, another migrant caravan left from Honduras heading north, but this one did not get very far. More than 3,700 Hondurans were turned back in Guatemala, where hundreds of police and military officials set up roadblocks and where, previously U.S. border agents may controversially have been involved in on-the-ground operations. Mexico had similarly deployed a heavy presence along its southern border to block passage.

The episode underscores changing migration dynamics in the Americas and around the world.

For one, it is testament to how the COVID-19 pandemic is fundamentally altering human movement. Guatemalan and Mexican government leaders cited the health crisis as the reason they halted the migrants’ path, although human-rights groups claimed the pandemic was being used as a pretext. Meanwhile, some migrants said that the poverty, violence, and corruption that prompted their flight had only gotten worse during the outbreak.

The caravan’s fate was also a sign of the changing posture by the Guatemalan and Mexican governments, which appear to have coordinated their response. Guatemala had previously done little to stop migrants’ passage, but this time President Alejandro Giammattei declared the travelers could “put us at serious risk” and suspended some constitutional rights to detain them. Mexico, meanwhile, has increasingly taken a tougher posture towards Central American migrants, partly in response to threatened U.S. tariffs.

Finally, the caravan highlighted how immigration has, oddly, faded from the limelight of U.S. politics. Trump built his 2016 campaign around restricting immigration, has taken more than 400 immigration-related executive actions, and can exploit a deep partisan divide on the issue. But with less than a month until the election, the president was oddly quiet about the new caravan. In fact, the politician who connected it to U.S. politics was Mexican President Andrés Manuel López Obrador.

Migration developments can be fluid, as the recent caravan demonstrated. The flows evolve in response to policy, politics, and broader circumstances, all of which are constantly changing.

Best regards,
Julian Hattem
Editor, Migration Information Source

The total number of unauthorized immigrants in the U.S. has declined from a peak in 2007 of abut 12.2 million to 10.5 million in 2017 (This from Pew, no estimates since then). Why?

Enforcement. It is most likely partly due to greater enforcement of immigration laws begun under Obama. The annual number of persons arrested in the U.S. interior doubled from the early 2000s to the second Obama administration; it has since leveled out or declined (even under Trump).

The U.S. economy. The falloff began very likely due to the 2008 financial crisis, which worsened work prospects in the U.S. But in the later 2010s, farming and hospitality industries, which hires many unauthorized workers, did well.

The Mexican economy. GDP growth in the past 20 years has been modest. There is a large informal employment sector. Education has incrementally improved. The country has had a higher percentage of young persons who did not complete high school than most comparable countries. However, it is possible that the odds for a young man to be schooled and get a job in Mexico have probably risen compared to coming illegally to the U.S. and finding employment.
See here and here.

The 10.5 million or so who remain are more likely committed to the U.S. for the long term. They include individuals who are currently DACA-protected (about 825,000) or could be protected with an expansion of the program, plus people who have been here for decades.

This is a relatively long post addressing an issue of great importance in this year in America: the contribution of immigration to social tensions. Is there a relationship? If so, what are the mechanisms? I summarize the case for a relationship and then suggest three somewhat overlapping mechanisms.

In the past 20 years, many researchers have looked at the impact of diversity on the level of social trust in a society. Much of that research focuses on ethnic/racial diversity, as opposed for example on religious and social class diversity. A recent review of 87 research articles found a statistically significant negative relationship betweem ethnic diversity, for example due to immigration, and social trust including social trust within groups.

The Center for Immigration Studies uses this review as evidence of ill effects of immigration.

A seminal study was done in around 2000 by one of America’s most respected social scientists, Robert Putnam. Fighting his personal pro-immigrant leanings, he warned, “The more ethnically diverse a residential context is, the less we trust …” He said the more racially diverse a community, the less trust exists among neighbors. Even trust within groups is lower in more diverse settings.

In thinking about these disturbing findings, it is useful to take several things into account:

First, the studies do not (as far as I can see) address other types of diversity – economic class, social class, religion. Would the emergence of an evangelical community within a traditional Christian domination community also affect social trust? Is increase in diversity related to, say, economic upheavals that erode trust?

Second, these studies do not deeply explore the mechanisms by which diversity reduces social trust within groups. There appears to be little attention given to psychology. I can think of three kinds of mechanisms.

One is the degree to which people sense that they can enjoy reciprocity with one another across ethnic boundaries. Diversity may erode one’s confidence in reciprocity in all instances.

Pre-existing low trust in public institutions may hasten the decline in trust. There appears to be a positive correlation between social trust and a society one the one hand, and trust in government, law and the police on the other hand. Pre-existing low trust in these institutions might aggravate a decline in social trust due to ethnic diversity.

A third possible mechanism is group politics. A culture of leadership may emphasize zero-sum game relations with out-groups, made up threats from outside, preach dependence on the leader to ward off threats, and enforce conformity, and undermine norms of government, law and policing. This might, in the face of diversity, increase psychological distress within the group. I have in mind Donald Trump.