A major looming problem for Americans is the accidental retirement plan - known to most people as the 401(k) - which began as a tax loophole to shelter the income of executives.

For decades, tens of millions of retired Americans were able to sustain themselves with some level of dignity and security through traditional pension plans, or defined benefit plans. As recently as 1983, 62 percent of Americans had pension plans.

A defined benefit retirement plan provides monthly pension checks - a predictable, stable income that retirees cannot outlive. In contrast, a defined contribution/401(k) retirement plan provides no established monthly pension, and it provides nothing to fall back on when the savings account is depleted.

The advent of defined contribution plans has allowed companies to shed pension plans. This wholesale change has yet to see a generation retire under its provisions, but as of today the future looks very bleak.

Pension plans hire professionals to make investments, have access to a wide variety of financial instruments that diversify risk and maximize returns, have lower fees for investment, and have a longer timeline to absorb the highs and lows of the markets. Studies consistently show that defined contribution plans, which do not have these tremendous advantages, underperform pension plans by a significant margin. And, this doesn't even take into account a final risk of defined contribution plan participants face: longevity risk, or the risk that they will outlive their assets.

Some politicians have been lining up to support the elimination of defined pension plans for new employees and force them into 401(k) plans. Strikingly, the reason is never given that the plan is better for the participant. Instead, the argument is that pension plans are unaffordable, and eliminating them will save the employer money.

Pension plans for Los Angeles police officers have been around since June 7, 1899, and have proven to work. The Los Angeles Fire and Police Pension system - even after the economic downturn - is currently 96.2 percent funded. The members contribute up to 9 percent of their pay biweekly. But even with this sizable contribution, the majority of the money needed to fund the pension systems comes from investments, not the contributions by the city or police officers.

In California, politicians opposed to pension plans are fond of citing figures that show a tremendous rise in contribution rates to plans such as CalPERS. The most commonly cited and deliberately misleading trick is to claim that the state's contribution has risen 2,000 percent since 2001. This claim uses as its starting point the year that required the lowest amount of contributions to CalPERS in decades - the end of a four-year period where the employers took a contribution "holiday," adding little or nothing to the pension system. (In 1996, the state contribution was $1.2 billion; by 2001, it dropped to $156 million.)

During those years, the pension reformers of today remained silent as the government shirked its pension obligation, helping to create the situation we see today.

Despite the ups and downs of the last 30 years, the system has paid hundreds of thousands of Californians their retirement check each month. And despite the current focus on pension bashing, California pays less of a percentage of payroll today than it did in the early 1980s. The current cost of pensions as a portion of state spending is about 2.5 percent.

As the jerry-rigged defined contribution plan lurches into its fourth decade, and as its failure to provide a secure retirement becomes more obvious, there is increasing demand to fix the structure of the plans. One idea is to mandate default investments into annuities that provide up to a lifetime stream of income.

However, annuities are usually insurance products and rely on the health of the underlying insurance company to pay off. The recent national financial crisis that revealed the fragility of many insurance companies cannot make this a comforting option. Other calls to mandate higher minimum contributions, or address poor asset allocation, reveal some of the fundamental flaws of a defined contribution plan.

By contrast, traditional pension plans have been a proven retirement vehicle for many decades. While ambitious politicians can blithely proclaim that the era of defined benefit plans is over, millions of Americans will soon find that the era of 401(k) plans is a disaster for those who want a secure and dignified retirement. It is increasingly clear that predictable and secure retirement incomes cannot be provided by 401(k) plans.