They basic serve as mills to churn out “research” tailored to their clients requirements.
If you want actual academic, nominally non-partisan, nominally unbiased research you go to a university and can sponsor a research topic and they’ll return the findings. The findings may be slanted towards what they think you want to hear, but normally will be grounded in some level of academic standards.
A think tank is an outfit who produce stuff that looks like academic research, but is nakedly partisan, openly biased and will give you the findings you’re paying for. The papers they produced are then used to give an air of credibility to the customer’s goals – the customer can point to these publications as though they were independent academic research findings and use them to support their agenda.
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