Undiscussable: a question in the Senate.

JUST hours after word got out that South Dakota senator Tim Johnson had fallen ill with a serious brain ailment, minority leader Mitch McConnell's office got in touch with Republicans around the Senate. The message: Do not--repeat, do not--talk about the political implications of Johnson's illness. Besides being genuinely concerned about Johnson, Republicans worried about their image and didn't want even to hint that they were seeking any advantage from their Democratic colleague's misfortune.

But the fact is, given the narrowness of the Democrats' 51-49 margin in the new Senate, Johnson's illness got people talking. If Johnson were to die, or had to leave the Senate, and if he were replaced by a Republican appointed by South Dakota's Republican governor, a 50-50 Senate would swing to GOP control, with Vice President Dick Cheney's tie-breaking vote. The stakes were clearly high. Still, when the Senate convened in early January--with Johnson still hospitalized--Republicans said pretty much nothing about the politics of it all.

It was a far cry from early 2001, when Democrats capitalized on what was known as the "Strom Thurmond Death Watch." At the time, the Senate was split 50-50, plus Cheney's vote, meaning that a switch of one senator would throw control into Democratic hands. That, of course, is what happened when Vermont's James Jeffords left the GOP in May 2001, but nobody knew that in January. Instead, Democrats acted on the possibility--the hope?--that South Carolina's Strom Thurmond, then 98 years old, would not survive the 107th Congress. If Thurmond died, his replacement would be chosen by South Carolina's Democratic governor, putting Democrats in power.

So when the Senate first got together in January 2001, Democrats insisted on placing a special provision in the rules. Their agreement with Republicans called for Senate committees to be split 50-50 between the parties, with the GOP holding the chairmanships. But the rules of the Senate, once made at the beginning of a new Congress, usually stay in place for two years. Knowing Thurmond's health--there were also eyes on North Carolina's Jesse Helms, then 79 and not doing well--Democrats came up with the following clause: "Such committee ratios shall remain in effect for the remainder of the 107th Congress, except that if at any time during the 107th Congress either party attains a majority of the whole number of senators, then each committee ratio shall be adjusted to reflect the ratio of the parties in the Senate ... and the committee chairmanships shall be held by the party which has attained a majority of the whole number of senators." Under the arrangement, if a Republican died--there weren't any Democrats on the death watch at the time--the turnover to Democratic control would be quick and clean.

Party supporters in the press got the message. "If Democrats, who control no branch of the federal government, seem oddly complacent these days, it may be because they believe they're holding an ace in the hole," wrote Slate editor Jacob Weisberg in March 2001. "Their secret weapon is the grim reaper." "Is it in bad taste to talk about the death of Strom Thurmond before he has actually died?" asked The Nation's William Greider. "Probably, but hey, everyone in the Washington power corridors seems to be talking about it." (Such talk was spurred on by a New York Times story headlined "A Hushed but Vital Issue: Thurmond's Health.")

Compare that with statements in the conservative opinion press after ...