In just the past few years, the whole American doctrine of urban warfare has changed. Where the strategy had been either to avoid cities or to destroy them, under the new doctrine the Pentagon's goal would be to isolate the cities, then selectively attack the pillars of the government. Fighting block by block is considered too risky and too likely to cement popular defiance. Rather, the military hopes Mr. Hussein's government would implode as he loses control over his loyalists.

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Historically, military forces attacking cities have suffered 30 to 40 percent casualties in the intensive fighting. In war games, the new approach has reduced estimated casualties to 10 percent.
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More than 2,500 years ago, the Chinese military strategist, Sun Tzu, warned that urban combat tires troops, courts casualties and voids a victory. "The worst policy is to attack cities," he wrote.

Today, Pentagon strategists have seen little to alter that analysis.

» U.S. Refines Plan for War in Cities