Alan Greenspan is the latest notable Washington expert to tell us that Social Security and Medicare need to be fixed - and soon. The question is, which first? Congress should start where there is vision, opportunity and leadership. George W. Bush provided the opportunity to fix Social Security and is pushing for reform using the considerable resources of the presidency.

Some, however, argue that Congress should start with Medicare because its problems are bigger and start sooner. Fine, let's start by not making a bad problem worse. The new drug benefit, which will add more than $8 trillion to the nation's debt, takes effect next year. Congress should repeal this entitlement and keep the existing prescription cards in place so that low-income seniors get the help they need. Then Congress should fix Social Security.

Social Security is easier to fix. It suffers from two problems: numbers and ownership. The program is heading toward insolvency because of an aging population and unaffordable benefit growth. High payroll taxes prevent many people from accumulating savings for retirement. And even those who disagree know what the possible solutions are. So why delay?

The best solution would bring ownership, control and choice to millions of families while limiting unaffordable benefit growth to something the system can afford to pay.

Medicare is harder: We don't fully understand all of the problems, let alone the possible solutions.

So let's capitalize on the president's vision and fix Social Security first. This won't be easy, however; we've all heard the hand-wringing, partisan bickering and ideological angst. All this when we know what the solutions are. Imagine trying to fix Medicare in such an environment.

The president's continued firm leadership is critical, for the American people and Congress. Congress should join him and fix Social Security's two problems to demonstrate to the American people that it can work in a bipartisan way to solve the easy problem. Then it should use that success to build momentum before tackling the greater problem of Medicare.

Alison Acosta Fraser is director of the Roe Institute for Economic Policy Studies at The Heritage Foundation (heritage.org).