The Republican Party looks at massive immigration, legal and illegal, as a source of cheap labor, satisfying a very important constituency.
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The Democratic Party looks at massive immigration, legal and illegal, as a source of voters.
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They view massive immigration as a massive infusion of potential voters for the Democratic Party, and therefore will do nothing, absolutely nothing to stop that flow of legal or illegal entrance into the country.
Because the worst of all worlds is when you pretend like you have an immigration policy, you make coming into the United States without our permission illegal, and then you actually don't enforce it.
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