Instead, the U.S. military's first salvos aimed directly at Iraq's leaders, including Saddam Hussein, involved about 40 Tomahawk missiles and several precision-guided bombs.
With 250,000 U.S. and coalition troops still encircling Iraq, the strikes were a small prelude to a massive assault that was to begin as early as Thursday, said two U.S. officials, speaking on condition of anonymity.
The cruise missiles were launched from Navy ships and submarines in the Persian Gulf and the Red Sea, while Air Force stealth fighter jets dropped the 2,000-pound precision-guided bombs, military officials said.
The timing of the initial attack may have been predictable, but the method wasn't. U.S. officials said Washington struck because it had specific, time-sensitive intelligence about the Iraqi leaders' location.
"This was not what we thought would happen," said Lawrence Korb, senior fellow at the New York-based Council on Foreign Relations. "This was out of the plan."
President Bush announced the start of the campaign in a televised address Wednesday night, saying U.S. forces had launched airstrikes against "targets of military importance." A U.S. military official said the strikes were aimed at "leadership targets."
U.S. officials, speaking in Washington on condition of anonymity, said the strikes didn't mean the main air offensive had begun, and said it was possible that other limited strikes could be launched before a larger offensive gets underway.
The announcement of the strikes initially appeared to catch even British officials unprepared. But Defense Secretary Geoff Hoon said later that Britain was "fully informed" by the United States before the strike and was involved.
Flight Lt. Peter Darling, spokesman for British military forces at Camp As Sayliyah, the Gulf command post for the U.S. Central Command, stressed that while hostilities had started, "this is not the start of the war."
"These air strikes were taking advantage of a window of opportunity based on intelligence reports," he said.
Harlan Ullman, a strategist at the private Center for Strategic and International Studies in Washington, said that at this early stage, there were three possible explanations for the attack:
"First, they went after Saddam and his leadership and hoped to end the war quickly by killing him," he said. "Second, the Americans were just sending a signal to the Iraqis that this was serious and this was their last chance because we were attacking in a very measured way suggesting that a lot more would follow; and third, we were just badly informed."
In describing the so-called "shock and awe" strategy, Pentagon officials have said in recent weeks that U.S. forces planned to drop 10 times the number of bombs they did at the start of the 1991 Gulf war.
Ullman said the strategy didn't necessarily require around-the-clock airstrikes now.
"The central point of 'shock and awe' is to get the leader first," he said. "If you get Saddam, that's game, set, match."
He cited the teachings of ancient military strategist Sun Tzu that "the best way to win a battle is not to fight it." Gen. Tommy Franks, who is leading the war, often quotes Sun as well.
Analyst Korb predicted that the heavy airstrikes would probably follow in the next day, but added that a limited strike could have its plusses even if it doesn't hit Saddam.
"Obviously it was a specific attack on a specific place," Korb said. "If he were in there, he's got to wonder who gave the information, and they have to wonder if he'll be safe anywhere."
Hours before the missile strikes Wednesday night, a helicopter carrying U.S. special forces crashed inside southern Iraq, a senior defense official said. There were no casualties and the troops on board were all taken out safely, said the official, who spoke on condition of anonymity. The official said the military was taking steps to destroy the helicopter rather than let it fall into Iraqi hands.
The incident makes clear the Pentagon was using a well-worn war tactic of dropping special commando forces behind enemy lines before the opening of the rest of the campaign.
Officials declined to say exactly where the crash occurred. But a widely discussed part of the war plan has been to send special forces into the country to secure oil wells, suspected chemical weapons sites and other strategic locations — as well as to search out Iraqi leadership.
A defense official also said a small plane headed from Iraq toward a Marine expeditionary force position in Kuwait but crashed short of its mark. The Marines donned gas masks because of fears that the plane could have been carrying chemical weapons, the official said. No agents were detected.
U.S. troops got their first real scare Thursday when Iraqi missiles streaked across the border into Kuwait, forcing the Americans to climb into protective suits and put on gas masks.
The American military said it used Patriot missiles to shoot down at least one Iraq missile. In the Kuwaiti desert, an Iraqi missile flew overhead and landed harmlessly in the desert.
No injuries were reported, and there was no immediate evidence the missiles had chemical or biological warheads. It was not clear whether the Iraqi missiles were Scuds or Al Samoud 2s.
The Iraqi attack came several hours after the United States' initial attack Wednesday night.
Just like the 1991 Persian Gulf War, the U.S. began with strikes from Tomahawk cruise missiles.
But Pentagon officials said the Tomahawks probably will be eclipsed by a new favorite bomb – the Joint Direct Attack Munition - made to fit the wish list of the Gulf War's commanders: cheap, plentiful, accurate and impervious to clouds, dust and smoke.
The strike on Baghdad included four 2,000-pound JDAM bombs dropped in pairs from F-117A Nighthawk stealth attack jets. The JDAM, extensively used in the war in Afghanistan, probably will make up the bulk of the thousands of bombs expected to rain on Iraq once the war begins in earnest.
Though its technology is 25 years old, the F-117A Nighthawk stealth fighter is still one of the most advanced planes in the world and is expected to play a large role in the war against Iraq.
Once it finishes its initial task, the Nighthawk will likely make way for heavier hitters including B-52s and the batwing-shaped B-2 bomber, which has more advanced stealth technology and is capable of attacking eight times as many targets on each mission.