If you were wondering what the White House has learned from three years of Iraq errors, the past week won't offer much comfort.

President Bush has been giving speeches assuring Americans that things are going well, with a few speed bumps. Secretary of Defense Donald Rumsfeld says that "the terrorists ... are losing." But the most unsettling event was the unveiling of a new national security strategy that reaffirms the 2002 Bush doctrine of pre-emptive war.

Pre-emptive war, you might recall, is the concept that America will attack its enemies — whether state or terrorist group — before they attack us, especially if we think they might use weapons of mass destruction. "We do not rule out the use of force before attacks occur," the strategy reads, "even if uncertainty remains as to the time and place of the enemy's attack."

On the surface, there is nothing exceptional about the doctrine. For example, in 1967, Israel pre-emptively attacked Egypt and Syria after Egypt had blocked one of Israel's main waterways and kicked out U.N. observers. One could imagine U.S. forces attacking terrorists who were sheltered by a weak state and were plotting to bomb an American city.

But the Bush doctrine is a much more explosive strategy that has already gotten us into big trouble in Iraq; it goes way beyond the concept of getting them before they get you.

In Iraq, the preemption doctrine was used to overthrow a ruler based on speculation about what he might do in the future. The assumption was that Saddam would get nuclear weapons and hand them off to terrorists who would use them against us. This was preventive war against a highly unlikely threat for which good intelligence was lacking. If other countries tried preventive war, imagine our reaction.

Everyone knows now that most White House premises for the war were specious. Even in 2002, the administration knew that intelligence about Saddam's nuclear weapons program was thin. It was ludicrous to think he would give a bomb to radical Islamists who wanted to destroy him, and whose bomb could be traced back to him.

The White House could have made a different case against Saddam: that he was an international pariah, in flagrant violation of U.N. resolutions, who would revive his nuclear program once sanctions were lifted and threaten the entire Mideast.

But the president chose to invoke a broad new doctrine that gave America carte blanche to overthrow any regime on the basis of evidence we chose. This doctrine unnerved even close allies. When we failed to find WMD in Iraq, it shredded Bush's credibility abroad.

Yet the doctrine of preemption survives as the guts of Bush's security strategy. More to the point, in a 49-page document, the doctrine is spelled out just two pages before the U.S. case against Iran.

The strategy paper states that America faces "no greater challenge from a single country than Iran"; speculation is rife as to whether Iran is the next candidate for preemption. The paper says America's concerns with Tehran's nuclear program can be solved only if Iran opens up its political system. This feeds the global buzz over whether America intends to bomb Iran's nuclear sites and topple the regime.

Bush's national security adviser, Stephen Hadley, insisted last week that the doctrine was not aimed specifically at Iran. He said preemption should not be seen "in the context of regime change," and he argued that America preferred to use diplomacy with Iran.

But the pre-emption doctrine is associated with Iraqi regime change at which we have proved hapless. Americans are not cut out to play a British-style imperial role. Yet Bush's language on Iran sounds as if we want to try it again in Tehran.

Even if Iraq has dulled the president's enthusiasm for regime change, making preemptive war the centerpiece of security doctrine is still a very bad idea — especially with Iran.

Such a doctrine no doubt has increased Tehran's appetite to build a nuclear weapons program swiftly. Presumably, Iran noticed that the doctrine doesn't threaten North Korea as harshly — perhaps because North Korea already has several bombs. The doctrine has certainly increased Iran's incentive to make trouble for Americans inside Iraq.

Moreover, as Francis Fukuyama points out in his new book, "America at the Crossroads," preventive strikes aren't likely to destroy budding nuclear programs. Iran learned a lesson from Israel's destruction of Iraq's Osirak reactor and has dispersed its program underground.

Fukuyama, a leading neocon turned critic of administration policy, adds another caution. Although an attack might slow Iran's nuclear program, the political damage would be immense. Nationalistic Iranians would rally round their regime. "The doctrine as a whole needs to be ... revised," Fukuyama says.

In other words, a broad pre-emption doctrine will rile our allies, whom we need by our side to isolate Iran. It will make more problems for national security than it solves. Iraq would seem a glaring case study of its failure.

However, there it stands, the centerpiece of our national security doctrine. Lessons not learned.

Trudy Rubin is a columnist and editorial board member for the Philadelphia Inquirer.