BECAUSE THE STOCK MARKET IS DOWN, people are saying the 401(k) has “failed.”

But the question is, “compared to what?” Public pensions are woefully underfunded — they’re promising defined benefits, but may not be able to deliver. Defined-benefit private pensions are dragging companies like GM, Ford and Chrysler toward bankruptcy. And Social Security is on an unsustainable trajectory, which the political system knows but which politicians can’t bear to confront. At least when 401(k) balances go down, the whole system isn’t rendered insolvent.