It all comes down to political risk versus market risk. Social security legally is merely a government welfare program masquerading as a quasi-private funded defined benefit pension plan. Social security bestows no legally protectable property rights on its participants. Hence the constitutional right of Congress to retroactively increase from time to time the Social Security retirement age and to means test. Moreover, the "bonds" in the phantom social security trust fund are bonds in name only. This is confirmed by a careful reading of the Social Security enabling statute, as well as two U.S. Supreme Court cases.
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