The war on drugs is a premier example.
Conservatives have the edge over liberals in that, generally, they're willing to assess evidence that contradicts their beliefs in candor and honesty. Not all, but most.
Liberals' beliefs are more robustly protected by the "fact-proof screen" (Eric Hoffer), because their beliefs tend to be a consequence of a vision of themselves as more moral and caring than those who disagree with them: to use Thomas Sowell's phrase, "a vision of differential rectitude." Therefore, to admit that they were wrong involves lowering themselves from an exalted moral plane to equality (or worse) with the rest of us, which is for many of them unthinkable, a debasement not to be borne.
There's no cure yet... but there is hope.
Freedom, Wealth, and Peace,
Francis W. Porretto
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