An earthquake strikes with no warning and in mere seconds can rearrange the landscape. But look beneath the surface and you'll find that hidden pressures had been building for a long time, finding release only when they could be contained no longer.
Such a moment has now come in Washington, D.C.
In just a week or two, once-solid Republican insistence on staying the course plotted by President Bush in Iraq has crumbled. Dismissive talk of the Democrats as Defeatocrats has been noticeably muted. Suddenly, everything has changed.
Last week, 11 Republican congressmen went to the White House, carrying an unwelcome message that they later made sure to share with the American public as well.
"Members really told the president in, I think the most unvarnished way that they possibly could, that things have got to change," Rep. Ray LaHood (R-Ill.) said afterward, citing a progress report due in September from Gen. David Petraeus as a coming moment of reckoning.
"We want a very candid report in September," LaHood said.
"We don't want politics mixed into it. And the way forward after September, if the report is not good, is going to be very, very difficult."
LaHood's comments echoed those of U.S. Rep. John Boehner of Ohio, the leader of House Republicans and long a defender of the president's approach.
"By the time we get to September or October, members are going to want to know how well this is working, and if it isn't, what's Plan B," said Boehner, who just a week earlier had attacked deadlines as "a timetable for American surrender."
The Republican leader in the Senate, Mitch McConnell of Kentucky, was equally blunt.
"I think there's going to be a different strategy in Iraq sometime soon, whether by congressional action or through the president taking a different tack, unless this surge is overwhelmingly successful," McConnell told The Washington Post.
"The jury's out," he said glumly. "It'll be reporting pretty soon."
Pressures leading to this earthquake have been building through four years of car bombs and suicide attacks, through the 2006 elections, through falling poll numbers for the president and an increasing realization that the Iraqi government is incapable of earning legitimacy in the eyes of its people.
But what touched off this sudden change? Most likely, it was an announcement by Petraeus, the U.S. commander in Iraq, that he intended to issue a frank progress report by September, a point the general drove home during recent briefings with members of Congress.
According to White House spokesman Tony Snow, the plan to issue such a report came from Petraeus himself, not from the president.
The president did, however, embrace the idea of a September reckoning. He welcomed it as a means of buying time, putting off the debate until at least the fall, a position he may come to regret.
"Decisions about the posture in Iraq need to be based upon conditions on the ground," Bush said recently. "And (there's) no better person to report about the conditions on the ground than somebody who is there, and that would be General Petraeus."
Bush will be president and commander in chief for another 20 months. But in effect, he has surrendered his self-bestowed title of The Decider.
As of last week, Petraeus has become The Decider. If the general reports in September that the surge is making progress — and if that claim can be seen as legitimate by the public — he could convince a reluctant Congress to fund military operations through one more budget cycle.
However, if Petraeus decides he cannot legitimately claim progress, including concrete steps by the Iraqi government to live up to its obligations, he will force a dramatic change of course that politically, the president will be helpless to prevent.
That's a huge burden for an unelected official to bear. Petraeus is not only free to be frank with the American people in a way that military officers never are, he is now obliged to be so.
It is an extraordinary situation in American history. A weak president and paralyzed Congress have in essence defaulted their roles, dumping that responsibility on a four-star general.
It is no reflection on Petraeus to note that is a deeply troubling development.
Jay Bookman is the deputy editorial page editor of the AJC. His column appears Mondays and Thursdays.
© 2007 The Atlanta Journal-Constitution