1. Immigration without assimilation. When newcomers remain socially, linguistically, or culturally separated from the broader population, integration becomes more difficult. France's disputes over secularism, religious identity, and integration illustrate these tensions. The United States faces related debates over language, civic identity, and expectations of newcomers.
2. The cost of public benefits. Immigration can increase government expenditures on education, healthcare, housing, and social services, especially in communities experiencing rapid population growth. The relevant fiscal question is whether those expenditures exceed the taxes and economic contributions immigrants make, and over what period.
3. Government capacity and public confidence. When immigration outpaces housing availability, school capacity, administrative resources, or integration programs, residents may conclude that their government has lost control of immigration policy.
There is evidence supporting your fiscal concern. The National Academies found that first-generation immigrants and their dependents imposed an estimated net cost of $57.4 billion annually on U.S. state and local governments during 2011–2013.