Sanctuary cities are an exercise in federalism at an extreme level. Federal officials tell cities that they must enforce federal laws to get federal funds. But the federal government often uses coercive powers of the purse to extract from cities and states what it wants. Many states would currently have a drinking age of 18, but for the federal government cutting off highway funds for non-compliance.
I have long favored a constitutional amendment that says simply:
The government of the United States cannot, through either the provision of or withholding of funds, direct, compel, or otherwise coerce a state or any subdivision thereof to take or refrain from taking any action or to make or refrain from making any law, regulation, or other legally binding order.
When the Supreme Court ruled several years ago that the federal government cannot compel local police to enforce federal laws, conservatives cheered. When the Supreme Court ruled just a few years ago that the federal government cannot compel states to expand Medicaid, conservatives cheered.
Conservatives should actually cheer on liberals wanting sanctuary cities because it ultimately advances our goals, not theirs. When they go to court and find favorable liberal judges giving legal sanction to sanctuary cities, the judges will not be able to carve out exceptions just for state level avoidance of federal immigration enforcement. The same legal logic will apply to other areas as well.
Read more at: Three Cheers for Sanctuary Cities | The Resurgent