White House spokesman Ari Fleischer refused to elaborate but said: "I think that justice comes in many different shapes and forms, and the President expressed his opinion about a couple of those."
Mr Bush has been preparing Americans for a protracted "crusade" to "root out" and rid the world of "evildoers" in the aftermath of suicide plane attacks on the World Trade Center's twin towers in New York and the Pentagon in Washington that left more than 5500 people dead or missing.
He has sought to educate the public about a new type of war against a different kind of enemy - a foe he demonises daily as barbarians who hide in holes and caves.
"It's an enemy that likes to hide and burrow in.
"Their network is extensive, there are no rules, it's barbaric behaviour," he said.
"They slit throats of women on airplanes in order to achieve an objective that is beyond comprehension."
Mr Fleischer said the President was referring to events on a fourth aircraft which crashed in western Pennsylvania apparently without reaching its intended target - the White House or the Capitol.
- REUTERS
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