What are some of the major surprises of the war?

» Coalition intelligence largely failed to anticipate the ferocity of and relentless attacks by the paramilitary fighters, the Fedayeen.

» The Pentagon and military assumed the Iraqi people would greet coalition forces as liberators. In general, they did not.

» The U.S. military had assumed that Saddam would draw coalition forces into a vicious urban war in Baghdad and that Saddam would fight to preserve his power. The Americans were shocked that Baghdad fell so quickly after the two "Thunder Runs" by Colonel Perkins's forces of the 3rd Infantry. The Iraqi regular army more or less crumbled.

» No chemical weapons were used. U.S. commanders presumed they would be attacked with chemical weapons, especially when they crossed the "Red Line" just outside of Baghdad. "Officers believed this to their marrow," says Thomas Ricks, The Washington Post's Pentagon correspondent.

» Ten months after the official end of major combat operations, American troops confront an open-ended conflict of guerrilla insurgency and suicide attacks in Iraq. Losses are mounting on all sides. Around 150 U.S. troops were killed in the invasion. Almost 400 have died so far in the aftermath.

How many civilians were killed in the six-week long invasion that toppled Saddam Hussein?

According to Mark Garlasco, who is conducting a study of the conflict for Human Rights Watch and was with the Pentagon's Defense Intelligence Agency during the war, no one knows exactly how many Iraqi civilians died. Estimates vary from almost 4,000 to nearly 10,000. The Pentagon did not count Iraqi casualties. For more on this issue, read the analysis section of this site.

In comparing the 1991 Gulf War to the 2003 Iraq war, what is the biggest difference in the air technology and air tactics?

The most significant change was that in the first Gulf War, coalition forces were largely dropping "dumb" bombs; in 2003 they were mostly dropping precision-guided "smart" bombs. This made the air campaign more effective, more able to strike targets precisely. And it also limited civilian casualties.

Was the air campaign a "shock and awe" strategy, as much of the media characterized it in the war's opening days?

No. The strategy of "shock and awe" as defined by leading theorists is esssentially an unlimited air campaign that calls for pounding the enemy to force surrender and devastating the country to the point where it's no longer capable of functioning as a society. Air planners in the 2003 Iraq war limited their target set and its intensity and duration in order to minimize Iraqi civilian casualties and destruction to the Iraqi infrastructure.

What was the single worst day of the war for American forces?

It was Sunday, March 23rd, four days into the invasion. The U.S. lost a total of 29 troops in the Marines' battle to take two key bridges in Nasiriya and in the ambush of the Army's 507th Maintenance Company when it accidentally took a wrong turn and drove into the city.

That night, in the western desert, 32 Apache helicopters were ordered forward to search out and destroy the Republican Guard. But the Iraqis sprang an ambush, and intense small arms fire brought down one Apache; the rest were forced to turn back with almost every helicopter damaged. The Republican Guard was largely unscathed.

(See Washington Post correspondent Thomas Ricks's comments on this day.)

During the war, how many attempts were made by coalition forces to kill Saddam Hussein and top Iraqi leaders?

50 attempts were made to kill top leaders in Saddam's regime. Not one was successful.

Two attempts were made on Saddam Hussein. One was on March 19th in the opening minutes of the war when Saddam was targeted at the Dora Farm complex in Baghdad where his daughters lived. The second was on April 7th near the al-Sar restaurant in the wealthy Al Mansour district in the west of Baghdad. Both attempts failed because the intelligence was poor.

What are some of the lingering questions and controversies of the war?

» Why were Pentagon planners so pessimistic about Saddam Hussein's strength and his intentions, and yet so optimistic about what would happen in Iraq after the war? Why did they seem to have a plan for executing the war, but no plan for what to do the day after it ended?

» What explains the failures of the Iraqi military? What was the thinking inside Iraq's military leadership? They appeared to capitulate and turn the war over to the paramilitary Fedayeen and irregular militias.

» The ground force was only half the size of the force in the 1991 Gulf War. Was this a mistake, and the major reason for the postwar difficulties that began with chaos and looting and has evolved into a widespread guerrilla insurgency?

» Was the surprise assassination attempt on Saddam Hussein on March 19th a mistake? There are critics who say it forced the cancellation of an all-important strategy to assassinate 55 top leaders at the very start of the war.