As it recently demonstrated in Iraq, the United States can boast the strongest and most technologically advanced military in the world. Its weapons systems, in particular, have reached a level of sophistication that perhaps no country can match. Smart bombs, guided by global positioning satellites, have become more accurate in recent years. New classes of weaponry have also been developed, such as the much touted E-bomb that destroys electronic devices and can cripple the ability of an enemy to communicate.

This backgrounder examines the state of the U.S. military and provides links to more information in Encarta Encyclopedia.

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Military strength
The four U.S. armed services--the Army, the Air Force, the Navy, and the Marines--have a combined force of about 1.4 million active-duty personnel. The U.S. Army, with 480,000 active-duty soldiers and 200,000 reservists, is one of the largest in the world. A few other countries have larger armies, but none can bring superior armaments or technology to a conflict limited to conventional, nonnuclear weapons. No other country can match the United States in naval power, and in air warfare* only Russia has fighter aircraft that can equal those of the United States.

In addition, the U.S. military operates elite units of specially trained and equipped commandos. In the U.S. Army, these units are known as Special Operations forces. Special Operations forces are exceptionally well-trained in weaponry, unconventional warfare, communications, and electronics. The Army sends Special Operations forces on high-risk missions, such as attacking bases behind enemy lines, destroying enemy command posts, and long-range reconnaissance. These units played a major role in defeating the Taliban and al-Qaeda forces in Afghanistan, and later in the 2003 war against Iraq.

The U.S. Navy also has highly trained special warfare forces for unconventional missions. They include SEAL (Sea-Air-Land) commandos and Special Boat Units. These forces perform risky missions such as beach and coastal reconnaissance, underwater demolition, attacking vessels along coastlines and in rivers, and hostage and prisoner rescue. Other countries also have elite units, but few have the training or equipment available to the U.S. Special Operations forces.

Among the technologically advanced weapons that the United States possesses are cruise missiles with a range of hundreds of miles, stealth aircraft* designed to elude radar detection, smart bombs* built to home in on precise targets, and the most advanced tanks in the world, such as the M1 Abrams tank that can accurately fire on targets even while moving. The U.S. military can pinpoint these targets with the most sophisticated reconnaissance and surveillance system in the world, including spy satellites, reconnaissance aircraft such as the Lockheed SR-71, and unmanned aerial vehicles that can also operate as offensive weapons.

Changes in U.S. military strategy
Since the end of the Cold War in 1991, the U.S. military has shifted its strategic emphasis from the prospect of fighting a nuclear war to the prospect of fighting simultaneously in two or three regional conflicts using conventional weapons. As a result of this strategic shift, the military began procuring more mobile equipment and establishing strategically located  bases to respond rapidly to a crisis anywhere in the world. Since the September 11, 2001, terrorist attacks on the United States, the military has also begun to focus on a global war against terrorism.

The U.S. military is no stranger to the fight against terrorism. Its first engagement in that regard came soon after the Civil War (1861-1865). During the Reconstruction period, the U.S. Army was ordered to fight the Ku Klux Klan, a terrorist organization that used violence to intimidate black Americans and prevent them from voting and holding political office in the South where they were newly emancipated.

In recent years, however, the U.S. military has more often been the victim of terrorism. In 1983, during a peacekeeping mission in Beirut, Lebanon, a suicide bomber crashed his explosives-filled truck into Marine headquarters in Beirut, killing 220 marines, 18 Navy personnel, and 3 Army troops. In 2000 suicide bombers belonging to the al-Qaeda terrorist network, led by Osama bin Laden, killed 17 U.S. sailors and wounded 39 others when they attacked the USS Cole anchored in Aden, Yemen.

Also on MSN Encarta
The Bush Doctrine: How does the new Bush doctrine change the future role of the U.S. military?
Weapons of Mass Destruction: How do they differ from conventional weapons, and how does the world guard against them?

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