Attention doomsday prophets: President Obama has initiated an executive-branch shakeup that could be consequential in the event of a nuclear apocalypse.

This week, Obama altered the lines of succession at the Departments of Commerce and Agriculture, the Environmental Protection Agency, the Office of Management and Budget, the Office of Personnel Management, the National Archives and Records Administration, and the Millennium Challenge Corporation for foreign aid.

The moves amounted to basic bureaucratic housekeeping, according to a White House official, who said the agencies had suggested the new lists as part of period reviews.

In other words: Obama is not girding for Armageddon.

Obama made the changes in a series of executive orders on Monday. For example, Deputy Secretary of Commerce Rebecca M. Blank is now next in line if anything happens to Commerce Secretary John Bryson, after Obama inserted her at the top of the list ahead of Commerce Department General Counsel Cameron F. Kerry, younger brother of Sen. John Kerry. And so on.

Lines of  succession in the federal bureaucracy run many positions and are extremely detailed. At the Environmental Protection Agency the new official line of succession runs 13 people. Last in line? Deputy Regional Administrator, Region II.

At the Dept. of Agriculture, Under Secretary for Farm and Agricultural Services Michael Scuse has wrested next-in-line status from Assistant Agriculture Secretary for Administration Pearlie S. Reed. At EPA,  General Counsel Scott Fulton has overtaken Assistant Adminstrator for the Office of Solid Waste and Emergency Response Mary Stanislaus as next in line behind EPA Administrator Lisa Jackson.

In perhaps the most stunning of these organizational eruptions, Obama added Alan C. Lowe, the director of the George W. Bush library, as the fourth and last in line behind national Archivist David S. Ferriero. In doing so, Obama bumped Jimmy Carter library Director Jay Hakes from the bottom of the list, after he was put there by George W. Bush in 2006.

Which means that bipartisanship is alive and well in Washington … at the bottom of the list of succession at the National Archives.

Update: This post originally misidentified the Commerce Secretary as Gary Locke, who is now Ambassador to China.