I've been sideline reading up on US immigration laws and policies and thought I'd share this:
https://www.cbo.gov/sites/default/files/109th-congress-2005-2006/reports/02-28-immigration.pdf
Relevant tidbits:
"The first federal law limiting immigration qualitatively was enacted in 1875, prohibiting the admission of criminals and prostitutes. The following year, in addressing efforts by the states to control immigration, the Supreme Court declared that the regulation of immigration was the exclusive responsibility of the federal government. As the number of immigrants rose, the Congress established the Immigration Service in 1891, and the federal government assumed responsibility for processing all immigrants seeking admission to the United States."
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"The Immigration and Nationality Act Amendments of 1965 abolished the national-origins quota system and established a categorical preference system. The new system provided preferences for relatives of U.S. citizens and lawful permanent residents and for immigrants with job skills deemed useful to the United States. However, it did
not abolish numerical restrictions altogether. For countries in the Eastern Hemisphere (comprising Europe, Asia, Africa, and Australia), the amendments set per-country and total immigration caps, as well as a cap for each of the preference categories. Although there was a total cap established on immigration from the Western Hemisphere, neither the preference categories nor per-country limits were applied to immigrants from the Western Hemisphere."
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"Under certain conditions, the United States may deny visas or admission on either a temporary or a permanent basis. For example, people may be denied admission on
the grounds of health, criminal history, security or terrorism concerns, the likelihood of their “becoming a public charge,” their seeking work in the United States without
proper labor certification and qualifications, prior illegal entry or violations of immigration law, lack of proper documentation, or previous removal from the country. Those grounds may be waived for certain admission categories."
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"The number of refugees admitted to the United States on an annual basis and the allocation of that number between countries are determined by the President in consultation with the Congress. In practice, U.S. policy has been to allow admission of at least half of the refugees identified by the U.N. High Commissioner for Refugees as being in need of resettlement."
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RE the visa program: "Visas for the diversity program are issued through a lottery administered by the State Department. Eligible countries are sorted into six geographic regions, and visa limits are set for those regions on the basis of immigrant admissions in the past five years and a region’s total population. Applicants must have either a high school diploma process (not all do so) may be granted lawful permanent or its equivalent or two years of work experience within the past five years. Countries that accounted for more than 50,000 immigrant admissions (under the numerically limited categories) during the previous five years are excluded from participation in the program."
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So it seems to me that just as Obama could unilaterally increase the number of immigrants and refugees accepted from various countries, so too could the next president lower them, including saying "none."
I am still waiting for the unconstitutional argument regarding Trump cutting off ME immigration.