WASHINGTON -- Do not fear a newfangled militarization of the Mexican-American border. For nearly three decades, U.S. border policy has been based on the premise that more armed patrols, more corrugated steel fencing, more helicopters, speedboats, night-vision goggles and infrared radar, more military ground sensors and aerial surveillance will one day stop the millions who desperately seek a better life in what they hope is a better place.

President Bush's plan to add a few thousand National Guard troops to this bristling contingent has little relevance. If years of building a high-tech arsenal and placing an army of guards along the southern border hasn't already amounted to a ``militarization,'' then what, exactly, would you call it? A failure, of course. But that is almost beside the point.

The war on immigrants now joins the war on drugs, the war on terror, the war in Iraq, the war on hurricanes and the war on bird flu in this distinction: They are complicated problems for which Bush looks to the Pentagon to provide a simple solution, and all-purpose political cover.

It is not some new militarization of the border that should worry us. It is the militarization of the American mind.

To say that the mentality predates this administration, as it does on the matters of drug interdiction and border control, is not to minimize the way in which a reflexive reach for the military option has characterized the Bush presidency. Since the 9/11 surprise attacks, the White House has been determined to use the military to prevent more surprises.

Bush's favorite constitutional clause is the one that names the president ``commander in chief."

The White House has cited Bush's power as commander in chief to detain American citizens indefinitely without charges or a show of evidence. It has used it to justify the vast military prison at Guantanamo Bay, Cuba, where hundreds are subject to indefinite incarceration. Bush says his role as commander in chief gives him unfettered power to circumvent laws against torture and to conduct secret abductions of suspects who are then jailed in secret prisons.

His authority as commander in chief, Bush says, allows him to eavesdrop on Americans' international communications and to amass a database of billions of phone numbers dialed by ordinary citizens -- not terrorism suspects -- who've done nothing to justify the intrusion.

A military thrust into Iraq was the only way Bush could see to solve the problem of Saddam Hussein, a chronic worry to the world but, it turned out, one whose militaristic ambitions had been tamed by economic sanctions. Now that it is clear the Iraq intelligence Bush used was either flawed or grossly manipulated for political purpose, the president seeks to install a military man, Gen. Michael Hayden, to head the CIA. Hayden's nomination is opposed even by some congressional Republicans who are wary of military involvement in a civilian agency.

The military has proved most useful when Bush seeks to conceal his own incompetence, and his government's chronic incapacity to plan for crises for which it has been forewarned.

When the Department of Homeland Security botched the federal response to Hurricane Katrina, the White House blamed Louisiana officials for their alleged failure to let him send troops quickly to New Orleans. The ensuing flap later served to distract from news that Bush had installed a hapless crony to head the Federal Emergency Management Agency, and that the White House had itself ignored warnings of a killer storm that had breached the city's levees. So naturally when the waters receded, Bush asked Congress to give him the power to use the armed forces as first responders to natural disasters.

Bush sees in the Pentagon the power to inoculate himself politically against catastrophes that have not yet unfolded and might not, with the sort of preparation government is supposed to do. Last October, he said he wanted to use the military to quarantine civilians in the event of a bird flu outbreak. ``And who best to be able to effect a quarantine?'' the president asked aloud at a news conference. ``One option is the use of a military that's able to plan and move.'' There is, of course, a term for this: martial law.

Marie Cocco's e-mail address is mariecocco@washpost.com.