Supporters say newcomers grow economies and keep ageing societies working. Opponents say fast immigration strains housing, budgets and public trust.
Immigration means people moving to live in a country where they were not born. Some come to work or study, some to join family, and some to escape war or persecution as refugees and asylum seekers. The debate is rarely about whether any immigration should happen. It is about how many people a country should let in, how fast, and on what terms.
Rich countries have swung between open and closed doors. In 1903 a plaque with Emma Lazarus's poem was placed inside the Statue of Liberty, welcoming “your tired, your poor, / Your huddled masses yearning to breathe free.”22 About twenty years later, the US Immigration Act of 1924 limited each nationality to two percent of its numbers in the 1890 census and shut out immigrants from Asia entirely.29
Today about 304 million people, 3.7% of the world's population, live outside their country of birth, almost double the 154 million of 1990.1 Permanent migration to the rich countries of the OECD hit a record 6.5 million people in 2023.6 Forced migration is growing too: 117.3 million people had been driven from their homes by the end of 2023, and 69% of refugees were living in a country next to the one they fled.18
In the United States, the immigrant population reached 53.3 million in January 2025, the largest number ever recorded and 15.8% of all residents. About 14 million immigrants in 2023 were in the country without legal permission.2 In December 2023, nearly 250,000 migrants were stopped at the border with Mexico, the highest monthly total on record,26 and the immigration court backlog passed 3 million cases.27 By June 2025, the immigrant population had fallen by more than a million, its first decline since the 1960s.2
Public opinion moves with events. In 2024, 55% of Americans wanted immigration reduced; by 2026 that had fallen to 29%, and 73% called immigration a good thing for the country.4 In Britain, net migration peaked at 944,000 in the year to March 2023,20 and Britons are now more likely than people in any other country to name immigration as their nation's top problem.21 Canada cut its 2025 target for new permanent residents from 500,000 to 395,000, partly to ease a housing shortage.12
Germany shows both sides at once. In 2015 Chancellor Angela Merkel told Germans “Wir schaffen das” (“We can do this”), and 1,164,000 people applied for asylum in 2015 and 2016.11 By 2024, 64% of the 2015 arrivals had jobs,10 yet the anti-immigration Alternative for Germany became the country's second most popular party in 2025.11
The main fault lines are who gains and who pays, how fast newcomers can be housed and included, and what rich countries owe to people born elsewhere. A major US review found that “the impact of immigration on the wages of native workers overall is very small,” but that some groups of workers and local budgets feel the effects more.5
Most immigration debates are won or lost on these four questions.
Both sides accept the economy gets bigger. They disagree about what that means for each person.
The same evidence, such as the Mariel boatlift, is read in opposite ways.
Even supporters of immigration argue about the pace.
A question of values. No statistic settles it.
The US: a record 53.3 million immigrants in January 2025, followed by its first fall since the 1960s.2
Canada: planned 395,000 new permanent residents for 2025, down from 500,000, to slow population growth and ease housing pressure.12
Germany: took in more than a million asylum seekers in 2015 and 2016; most of the 2015 group now work.1011
The UK: net migration peaked at 944,000 in the year to March 2023, then fell to an estimated 345,000 in 2024.20
Japan: a record 2.3 million foreign workers in October 2024, as it tries to fill labor shortages made worse by an ageing population.13
Debate tip: comparing countries is useful evidence on both sides. Pro can point to Germany's job figures and Japan's turn toward foreign workers; Con can point to Canada and the UK, which both cut numbers after rapid growth.
For class or club discussion. There are no right answers; ask for reasons and evidence.
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