The locals say that immigrants take away their jobs by working for cheap. Insofar as this is true, it frees capital for new kinds of initiatives—new kinds of interesting work that locals transition to. And it's precisely among the immigrants that new entrepreneurs are found. Successful companies such as Google, Zoom, WhatsApp, Uber, PayPal, Instagram, eBay, YouTube, Comcast, Intel, Bloomberg, Moderna, DreamWorks, Forever 21 and many others were started by immigrants or their children.
The locals also say that immigrants import bad ideas with them. This issue is addressed in full in the article Balancing Open Borders and Political Ideals. The gist: limit voting rights for N generations. This ensures the country’s core values remain dominant as the immigrant population gains political representation.
What should be N? Setting N to 3 (grandchildren of immigrants) would appear sufficient, but there are corner cases, such as cross marriages and immigrants traveling back home for extended periods. Increasing N to 5 would take care of all such cases.
Another argument against immigration is that it opens the door to criminals. However, it’s not true that proportion of criminals is higher in immigrant population. There are numerous studies on this. Numerous studies support this. Here's a summary from Google's Search AI:
Based on numerous studies and analyses, the overwhelming consensus is that immigrants in the United States, regardless of their legal status, are less likely to commit crimes compared to native-born citizens.
What about horrors such as rape that followed the Syrian migrant wave to Europe a decade ago? Countries must increase its police force in proportion to the prevalence of dangerous ideologies, and those who commit crimes must be prosecuted—punished severely and made public examples of. The rule of law must be upheld loudly. Instead, the issue was hushed in an attempt to avoid escalating hostilities.
The Western world must drop the idea that all cultures have merit. They do not: some are good and some are evil. We must make sure that immigrants know they have come to a better culture and should shed their wrong ideas. Although a government can’t dictate what people think, it does have an opportunity to state things in court through pronouncements by judges. The private media will cheer and follow suit of its own accord.