> the deduction began as an unplanned technicality. When the federal government first levied income taxes in 1913, Congress allowed Americans to deduct from their taxes the cost of all interest payments. This is standard policy for corporations: the government only wants to tax profits—not money spent on loans for tractors or a new office. In 1913, the government allowed deductions on all interest—probably because all interest payments were business-related. No one took out car loans in 1913 or paid interest on credit card debt, and the majority of mortgages were for farms.

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