So we have our answer - it wasn't caused by "imperialism", but by specific laws passed by politicians, against the will of natives [1]. And we know how the economics worked out in countries that bothered to look [2].
[1] Between 1962 and 1971, as a result of popular opposition to immigration by Commonwealth citizens from Asia and Africa, the United Kingdom gradually tightened controls on immigration by British subjects from other parts of the Commonwealth. - https://en.wikipedia.org/wiki/British_Nationality_Act_1948
Those laws were themselves a direct consequence of imperialism. Without the empire there would have been no Commonwealth migration to legislate about. Public opinion might explain why the laws were tightened, but it’s irrelevant to the causal chain.
Speaking of causality, Kirkegaard did not perform any kind of causal inference, so his analysis is based on correlation only, not on identified causal effects. He compares group averages and finds correlations with outcomes like employment or fiscal contribution, but that’s descriptive statistics. There are no counterfactuals, no identification strategy, and no attempt to separate selection effects, institutional factors, or assimilation dynamics. In other words, it’s not causal evidence — just patterns that he interprets as if they were.
Yet somehow the Ottoman and Japanese empires didn't "directly cause" such laws in Turkey or Japan, so obviously this is not "after rain, the streets are wet" type causality, but more like "the safe was unlocked, which caused me to steal the contents" "causality".
> Public opinion [..is] irrelevant to the causal chain.
Public opinion is irrelevant to what laws and policies are enacted in a "democracy". It would be hilarious if it wasn't so true.
The Ottoman empire caused tons of Muslim migrants to enter its core provinces. Empires always managed and reshaped migration. The Romans resettled conquered peoples across their empire to strengthen borders and repopulate cities. The Habsburgs moved ethnic groups into borderlands against the Ottomans. The Russian Empire orchestrated mass movements of Tatars, Circassians, and others. In all these cases, imperial expansion created migration streams that later fed into demographic and political conflicts.
Nice moving of goalposts. Meanwhile despite the Russian and Japanese empires, Moscow and Tokyo are 90% [1] and 95.4% [2] native, respectively, and despite the Ottoman Empire, 93.2% of Turkey is either populations native to the region (Turks, Kurds, and Yoruks) or from immediately adjacent regions (Tatars and Azerbaijanis). 95% if we count "Arabs" as adjacent, or even more, depending on what "other" is [3].
That's equivalent to if the UK was 95% English, Welsh, Scottish, Irish, with some French, Germans, Danes, and Swedes. But we're supposed to pretend India and Pakistan moving into England is the same as population exchange with neighbors.
And that's still not "direct causation". But you ignore that, because you want to make it seem inevitable, when it is anything but.
Those percentages are shaky (especially Tokyo and Turkey), and even if roughly true, they don’t negate the fact that empires like the Ottoman, Roman, and Russian actively engineered huge population movements. High present-day homogeneity doesn’t mean migration wasn’t empire-driven.
[1] Between 1962 and 1971, as a result of popular opposition to immigration by Commonwealth citizens from Asia and Africa, the United Kingdom gradually tightened controls on immigration by British subjects from other parts of the Commonwealth. - https://en.wikipedia.org/wiki/British_Nationality_Act_1948
[2] https://emilkirkegaard.dk/en/2024/02/fiscal-impact-of-immigr...