Suppose, just suppose, that Hillary Clinton's health-care reform is a ruinously expensive failure. I know it's hard to believe, but this sometimes happens with government programs.

So, assume health-care reform fails. The doctors hate it, the patients hate it, employers hate it. Insurance-dodgers are burning their health cards in front of the White House.A delegation of top congressional Democrats asks for a private audience with President Clinton. After some initial throat-clearing, House Speaker Tom Foley opens the meeting:

"Mr. President, health care has been a horrible mistake. We'll clean up the legislative mess and pass a few goodies to calm the public, but, the fact is, somebody has to take the fall."

After a while, Clinton asks, "What do you mean `take the fall'?"

"Hillary," says the speaker. "She has to go. Health care was her baby, and the public identifies her with it. She's killing your chances of re-election, but, more importantly, she's killing ours. Put simply: If she stays, you go."

The congressional delegation quickly explains that this doesn't mean that the Clintons have to get divorced, just that Hillary has to step down as first lady.

Foley growls, "Not now," when Sen. Joe Biden, D-Del., chairman of the Judiciary Committee suggests that future first ladies be subject to Senate confirmation.

After stepping down, Hillary Clinton would move a couple of blocks down Pennsylvania Avenue to a residential hotel catering to transient government workers and do what others burned by Washington have done before her: She writes a book and plots revenge.

Thanks in part to Hillary Clinton, the post of first lady had become essential to running the White House, much like the chief of staff and the chief counsel, and the job could not be left unfilled.

How best to fill it?

The nation could follow the 1947 law of succession, as amended, in which case Tipper Gore, the wife of the vice president, would become first lady.

Heather Foley, the wife of House Speaker Tom Foley, would then become second lady.

That would leave the speaker in the lurch, because Heather Foley is his chief of staff, though unpaid because of congressional nepotism rules.

Still hewing to the law of succession, the next in line is the president pro tempore of the Senate, currently Robert Byrd of West Virginia, who might have mixed feelings about seeing Erma Byrd depart to the rival camp.

The possibility for mischief is serious because the succession goes down through the Cabinet - State, Treasury - and here we run into problems because the next two secretaries in line, Les Aspin at Defense and Attorney General Janet Reno, are single.