Brian Flemming has gone to the trouble to document the day by day efforts of Bush to get to the bottom of this.

76 Days

July 14, 2003. President Bush discovers a breach of national security. Two "senior administration officials" have apparently exposed the identity of a covert CIA operative while attempting to discredit one of Bush's critics.

President Bush immediately swings into action to cure this shocking, illegal breach. Here is a detailed, day-by-day chronology of the president's decisive action:
[more]

  thanks to Eschaton

It's worth looking at a Salon ad to read Daniel Ellsberg's reaction to Bush's plumbers...

"The plumbers are back"
The man who sparked Watergate, Daniel Ellsberg, has deja vu watching the Bush administration try to spin the Plame leak.

Watching the Valerie Plame scandal unfold, Daniel Ellsberg has déjà vu. In 1971, Ellsberg became the most famous leaker in American history with his release of the 7,000-page Pentagon Papers, a Defense Department study of the country's sordid involvement in Indochina. Besides revealing the lies and hypocrisy of American policy in a war its leaders knew was futile, Ellsberg's leak led Nixon to create the plumbers, the dirty tricks squad that broke into Ellsberg's psychiatrist's office looking for information to discredit him. Nixon's henchmen would use similar tactics against Democratic opponents, leading to the Watergate scandal and the president's downfall.

Today, Ellsberg says, America is in the early stages of a similar crisis. Once again, he says, the country is embroiled in a foreign war for murky reasons. Once again, he says, the White House has justified its policy with lies, and is smearing a whistle-blower who exposed those lies.
[more]