Predictably, President George Bush's push to reform Social Security has encountered stiff resistance. Some Democrats are even celebrating the rising perception that reform's chances for this year are in serious decline. Yet if our elected leaders squander this chance to address the inexorable demographic challenges facing the largest entitlement program in U.S. history, the biggest losers won't be President Bush and other reform boosters, but the American people.

If those growing giddy over that potential outcome have a better idea of how to save Social Security than the reform proposals advanced by President Bush and others, they should present them. If not, they should explain how Social Security can possibly survive the status quo over the next few decades.

Repeating the obvious, President Bush put the system's problems in simple, indisputable numeric terms during a news conference Thursday night: "Today, there are about 40 million retirees receiving benefits. By the time all the baby boomers have retired, there will be more than 72 million retirees drawing Social Security benefits."

He added: "And to compound the problem, there are fewer people paying into the system. In 1950, there were 16 workers for every beneficiary; today there are 3.3 workers for every beneficiary. Soon there will be two workers for every beneficiary."

The president wants to offset those numbers with a "system in the future where benefits for low-income workers will grow faster than benefits for people who are better off." He later said: "Obviously it is means-based when you're talking about lower income versus wealthier income."

The idea prompted headlines and outcries about "benefit cuts." But at least under the president's plan, those cuts would be imposed on wealthier Americans, while benefits for poor Americans would be preserved.

Sen. Lindsey Graham, R-S.C., a convincing champion of reform, rightly praised that "progressive" approach as "an absolutely essential component in saving Social Security from bankruptcy."

And again, those who don't see the president's proposal, which includes giving younger workers the alternative (in other words, on a voluntary basis) of private accounts, as the best solution to Social Security's problems should offer counter-solutions. Nobody, however, should ignore the fiscal realities that require any effective proposal to include some level of sacrifice.

That level of sacrifice will become higher the longer Washington waits to deal with the challenges facing Social Security. Sen. Graham observed this week: "No Democrat is going to negotiate until the president takes his lumps."

No doubt that's the unfortunate political reality. But leaders in both parties should realize that any short-term political gains in the Social Security debate would ultimately be overwhelmed by devastating long-term consequences if the system isn't fixed.