Pity the opponents of Social Security reform. Now that President Bush has spelled out some details of his plan to keep the program from sliding into insolvency, it’s going to be harder for them to demonize it. It’s always easier to fear-monger the unknown.

Younger workers should be especially cheered, as the Bush plan would let them use a portion of their Social Security taxes to fund Personal Retirement Accounts (search). As the president explained in his State of the Union address, these accounts will provide larger checks than they can expect under the current system.

Older Americans worried that the reforms might include cuts in their benefits were reassured. The president made quite clear that retirees and soon-to-be retirees (workers aged 55 and up) would receive every cent they’ve been promised — including annual cost-of-living increases.

The president’s plan offers younger workers access to a “blended” retirement program. Workers electing to establish PRAs would still pay the lion’s share of their Social Security taxes into the government till. The government, though, would pay reduced benefits based on their earnings history. Call this benefit Social Security Part A.

But these workers also could invest up to 4 percent of their Social Security taxes in PRAs. To minimize risk and confusion — and to obviate the need for personal savvy about stocks and bonds — PRA investment choices would be restricted to a relatively small number of diversified funds.

The base portfolio is expected to consist of 50 percent stock index funds, 30 percent corporate bond index funds and 20 percent government bonds. Based on historical trends, this mix would yield about 4.6 percent annually (adjusting for inflation and subtracting administrative fees) — about 50 percent more than the average amount earned by government bonds.

Upon retiring, workers would be required to dip into their PRAs to purchase annuities that would provide benefits for what we’ll call Social Security Part B. Retirees would be required to annuitize enough of their PRA to produce a total monthly benefit (when combined with Part A payments) sufficient to keep their income above poverty level. But they would be free to use the remainder of their PRAs as they wish.

They might elect to pay themselves higher benefits, either by annuitizing more of their PRA savings or simply by making regular withdrawals from their accounts. They might leave most of it in the account, continuing to build a nest egg that could be tapped for emergencies or left to their families.

And that, of course, is the big advantage of letting workers establish personal accounts. The money they earn and put aside in PRAs remains their money. They can pass along to their families whatever is left over when they die. This is a major improvement over the current system, in which workers can pay into the system for decades and die without ever collecting a penny or being able to pass any of it on to their loved ones.

For this reason, the president’s plan should be especially attractive to low-income workers. Today’s high Social Security tax rates bleed them of the ability to save independently. But by directing 4 percent of their income into accounts that they own, even low-income earners can build significant nest eggs. When passed on to their children or grandchildren, these savings can free families previously trapped in the cycle of intergenerational poverty.

Importantly, the president made clear that participation in the PRA plan is strictly voluntary. But he also made clear that Social Security can’t continue unreformed. Soon, there will be too few workers supporting too many retirees.

The current system promises to give increasingly generous benefits, for increasingly long periods of time, to an increasingly large number of people — and to pay for it by taxing a proportionately smaller number of people. It simply can’t be done.

Social Security has worked well for generations of Americans, but 21st century demographics doom it to insolvency. By making PRAs an integral part of the system, the Bush plan offers younger workers access to the same level of retirement security enjoyed by their parents and grandparents.

The approach is far preferable to the alternatives, which consist mainly of various combinations of massive tax increases and sharp benefit cuts.

The ball is now in Congress’ court, but the president’s role is far from over. As lawmakers work out the details of Social Security reform, they must bring future guaranteed benefits in line with what today’s and tomorrow’s workers can afford to pay. Unless the administration insists that Congress do so, the president’s plan will fall short of its goal —permanently fixing Social Security.

David C. John is a senior research fellow for Social Security at The Heritage Foundation, a Washington-based public policy research institute.