Having already wrecked a legendary American city, Hurricane Katrina may now be invoked to undermine a fundamental principle of American law: When it comes to domestic policing, the military should be a last resort, not a first responder.
On Sept. 26, President Bush urged Congress to consider revising federal laws so that the U.S. military could seize control immediately in the aftermath of a natural disaster, noting that "it may require change of law."
The law the president seems to be referring to is the Posse Comitatus Act, the longstanding federal statute that restricts the government's ability to use the U.S. military as a police force.
Sen. John Warner, R.-Va., chairman of the Armed Services Committee, also has signaled his desire to change the law.
Pentagon spokesman Lawrence Di Rita called Posse Comitatus a "very archaic" statute that hampers the president's ability to respond to a crisis.
Not so. The Posse Comitatus Act is no barrier to federal troops providing logistical support during natural disasters. Nor does it prohibit the president from using the Army to restore order in extraordinary circumstances -- even over the objection of a state governor.
What it does is set a high bar for the use of federal troops in a policing role. That reflects America's traditional distrust of using standing armies to enforce order at home, a distrust that's well-justified.
There are good reasons to resist any push toward domestic militarization.
As one federal court has explained: "Military personnel must be trained to operate under circumstances where the protection of constitutional freedoms cannot receive the consideration needed in order to assure their preservation. The Posse Comitatus statute is intended to meet that danger."
Army Lt. Gen. Russell Honore, commander of the federal troops helping out in New Orleans, seemed to recognize that danger when he ordered his soldiers to keep their guns pointed down: "This isn't Iraq," he said.
Soldiers are trained to be warriors, not peace officers -- which is as it should be. But putting full-time warriors into a civilian policing situation can result in serious collateral damage to American life and liberty.
It can also undermine military readiness, because when soldiers are forced into the role of police officers, their war-fighting skills degrade. That's what the General Accounting Office concluded in a 2003 report looking at some of the homeland security missions the military was required to carry out after Sept. 11, 2001.
According to the report, "While on domestic military missions, combat units are unable to maintain proficiency because these missions provide less opportunity to practice the varied skills required for combat and consequently offer little training value."
The GAO also concluded that such missions put a serious strain on a military already heavily committed abroad.
American law calls for civilian peace officers to keep the peace, or, failing that, National Guard troops under the command of their state governors. So perhaps we should stop treating the National Guard as if it's no different than the Army Reserve.
As Katrina made landfall, there were 7,000 Louisiana and Mississippi Guard troops deployed in Iraq. Among them were 3,700 members of Louisiana's 256th Mechanized Infantry Brigade, who took with them high-water vehicles and other equipment that could have been put to better use in New Orleans.
The Guard personnel at home had only one satellite phone for the entire Mississippi Gulf Coast when Katrina initially hit -- because the others were in Iraq.
Lt. Gen. Steven Blum, chief of the National Guard Bureau, noted that had the Louisiana Guard "been at home and not in Iraq, their expertise and capabilities could have been brought to bear."
Disaster relief and responding to civil disturbances are core missions for the Guard; attempting to establish democracy in the Middle East is not.
The Katrina tragedy ought to be an occasion for rethinking a number of federal policies, including our promiscuous use of the Guard abroad. Instead, Washington seems poised to embrace further centralization and militarization at home.
That has the makings of a policy disaster that would dwarf Hurricane Katrina.