Opening attack

On March 20, 2003 at approximately 02:30 UTC or about 90 minutes after the
lapse of the 48-hour deadline, at 05:30 local time, explosions were heard in
Baghdad. There is now evidence that various Special Forces troops from the
coalition crossed the border into Iraq well before the air war commenced. At
03:15 UTC, or 10:15 p.m. EST, U.S. President George W. Bush announced that
he had ordered the coalition to launch an "attack of opportunity" against targets
in Iraq.

Before the invasion, many observers had expected a lengthy campaign of aerial
bombing in advance of any ground action, taking as examples the Persian Gulf
War or the invasion of Afghanistan. In practice, US plans envisioned
simultaneous air and ground assaults to decapitate the Iraqi forces as fast as
possible (see Shock and Awe), attempting to bypass Iraqi military units and
cities in most cases. The assumption was that superior Coalition mobility and
coordination would allow the US-led Coalition to attack the heart of the Iraqi
command structure and destroy it in a short time, and that this would minimize
civilian deaths and damage to infrastructure. It was expected that the
elimination of the leadership would lead to the collapse of the Iraqi Forces and
the government, and that much of the population would support the invaders
once the government had been weakened. Occupation of cities and attacks on
peripheral military units were viewed as undesirable distractions.

Following Turkey's decision to deny any official use of its territory, the US-led
Coalition was forced to abandon a planned simultaneous attack from north and
south, so the primary bases for the invasion were in Kuwait and other Persian
Gulf nations. One result of this was that one of the divisions intended for the
invasion was forced to relocate and was unable to take part in the invasion until
well into the war. Many observers felt that the Coalition devoted insufficient
numbers of troops to the invasion, and that this (combined with the failure to
occupy cities) put them at a major disadvantage in achieving security and order
throughout the country when local support failed to meet expectations.

The invasion was swift, with the collapse of the Iraq government and the military
of Iraq in about three weeks. The oil infrastructure of Iraq was rapidly secured
with limited damage in that time. Securing the oil infrastructure was considered
of great importance to funding the rebuilding of Iraq after the invasion ended. In
the first Persian Gulf War, while retreating from Kuwait, the Iraqi army had set
many oil wells on fire, in an attempt to disguise troop movements and to distract
Coalition forces. Prior to the 2003 invasion, Iraqi forces had mined some 400 oil
wells around Basra and the Al-Faw peninsula with explosives. The British Royal
Marines 3 Commando Brigade launched an air and amphibious assault on the
Al-Faw peninsula during the closing hours of 20 March to secure the oil fields
there; the amphibious assault was supported by frigates of the Royal Navy and
Royal Australian Navy. The 15th Marine Expeditionary Unit, attached to 3
Commando Brigade, attacked the port of Umm Qasr. The British 16 Air Assault
Brigade also secured the oilfields in southern Iraq in places like Rumaila.
Despite the rapid advance of Coalition forces, some 44 oil wells were destroyed
and set blaze by Iraqi explosives or by incidental fire. However, the wells were
quickly capped and the fires put out, preventing the ecological damage and
loss of oil that had occurred at the end of the Persian Gulf War.

In keeping with the rapid advance plan, the U.S. 3rd Infantry Division moved
westward and then northward through the western desert toward Baghdad,
while the 1st Marine Expeditionary Force moved along Highway 1 through the
center of the country, and 1 (UK) Armored Division moved northward through
the eastern marshland.

Initially, the U.S. 1st Marine Division fought through the Rumaila oil fields, and
moved north to Nasariyah--a moderate-sized, Shi'ite dominated city with
important strategic significance as a major road junction and its proximity to
nearby Talil Airfield. The U.S Army 3rd Infantry Division defeated Iraqi forces
entrenched in and around the airfield and bypassed the city to the west. On 23
March, U.S Marines and Special Forces units pressed the attack in and around
Nasiriyah. During the battle an Air Force A-10 was involved in a case of
fratricide that resulted in the death of six Marines. Because of Nasiriyah's
strategic position as a road junction, significant gridlock occurred as U.S forces
moving north converged on the city's surrounding highways. With Nasiriyah and
Tallil Airfield secured, U.S. forces gained an important logistical center in
southern Iraq, establishing a base some 10 miles outside of Nasiriyah through
which additional troops and supplies were brought. The 101st Airborne Division
continued their attack north behind the 3rd Infantry Division, and the 82nd
Airborne Division began to consolidate in and around Talil airfield for further
operations. By 27-28 March, a severe sand storm slowed the U.S advance as
the 3rd Infantry Division fought on the outskirts of Najaf and Kufa, with
particularly heavy fighting in and around the bridge adjacent to the town of Kifl
before moving north toward Karbala.

Farther south, the British 7 Armored Brigade ('The Desert Rats') fought their
way into Iraq's second-largest city, Basra, on 6 April, coming under constant
attack by regulars and Fedayeen, while the 3rd Parachute Regiment cleared
the 'old quarter' of the city that was inaccessible to vehicles. The entering of
Basra had only been achieved after two weeks of conflict, which included the
biggest tank battle by British forces since World War II when the Royal Scots
Dragoon Guards destroyed 14 Iraqi tanks on 27 March. Elements of 1 (UK)
Armored Division began to advance north towards U.S. positions around Al
Amarah on 9 April. Pre-existing electrical and water shortages continued
through the conflict and looting began as Iraqi forces collapsed. While British
forces began working with local Iraqi Police to enforce order, REME (Royal
Electrical Mechanical Engineers) and Royal Engineers of the British Army
rapidly set up and repaired dockyard facilities to allow humanitarian aid began
to arrive from ships arriving in the port city of Umm Qasr.

After a rapid initial advance, the first major pause occurred in the vicinity of
Karbala. There, U.S. Army elements met resistance from Iraqi troops defending
cities and key bridges along the Euphrates River. These forces threatened to
interdict coalition logistical supply routes as U.S. forces moved north. By the
end of March, elements of the 82nd Airborne Division augmented with a
mechanized infantry battalion task force of the U.S. 1st Armored Division began
diversionary assaults in and around the city of Samawah in order to divert Iraqi
forces that may have otherwise threatened the extended rear of the coalition's
lead elements. Meanwhile, the U.S. 101st Airborne Division and infantry
elements of the U.S. 1st Marine Division, supported by an armored battalion
task force of the 1st Armored division and U.S. Marine and Army air support,
attacked and secured the cities of Najaf and Karbala in order to prevent any
Iraqi counterattacks from the east. These attacks effectively protected the
eastern flank and rear of the 3rd Infantry Division, which allowed the western
flank of the invasion to re-supply and continue its advance north through the
Karbala Gap and on toward Baghdad, where U.S Marine and British forces had
already begun a preliminary assault on the outskirts of the city.