The American Revolution, also known as the War of Independence, was the war that won America its independence from Great Britain.  After the end of the expensive French and Indian War (1763), Britain imposed new taxes and trade restrictions on the colonies , which fueled growing resentment and added to the colonists' objection to their lack of representation in the British Parliament.  The war began at Lexington and Concord, Massachusetts, when the American minutemen clashed with British troops.  Even though, at times when the American Continental Army were utterly defeated and morale was extremely low, General George Washington was able to maintain the army intact and strike back at Battles of Trenton and Princeton on Christmas Eve of 1776.  On July 4, 1776, the Continental Congress issued the Declaration of Independence, proclaiming American independence from Britain.  When the Americans under the brilliant Benedict Arnold defeated Burgoyne at Saratoga (1777), the French entered the war on the American side.  The war ended when General Cornwallis surrendered to Washington at Yorktown in 1781.  With the Treaty of Paris (September 3, 1783), Britain recognized the independence of the U.S. east of the Mississippi River and ceded Florida to Spain.

        The Quasi War was an undeclared naval war between the newly born United States and France.  Tensions had increased between the two nations when French ships harassed and interfered with American trade.  France further humiliated the United States in the XYZ Affair when they refused to receive American diplomats.  President Adam ordered American naval ships to attack French ships on the high seas.  The naval confrontation ended with France unofficially agreed to stop the harassment of American ships. 

        The U.S. refused to continue paying tribute to the rulers of the North African Barbary Coast states, which had bought immunity from pirate attacks in the Mediterranean. The pasha of Tripoli demanded greater tribute and then declared war on the U.S. (1801).  President Thomas Jefferson ordered the U.S. military to attack the pirates' stronghold.  A U.S. naval squadron was sent to Tripolitan waters and fought several skirmishes, including a raid by Stephen Decatur. A U.S. naval blockade and an overland expedition from Egypt ended the war with a peace treaty favorable to the U.S.

        The Napoleonic Wars in Europe caused the British to establish the blockade around the North Sea.  American ships were stopped and forcefully searched and sailors in the United States Navy were frequently impressed into the service of the Royal Navy.  This caused a storm of fury and protest back in America.  President Jefferson issued the Embargo Act, and stopped trade with both Britain and France, but this hurt the Americans more than the British or French.  Finally, in 1812, the War Hawks in Congress pressured President Madison to declare war on Britain.  The war dragged on for two years during which time saw both American victories and setbacks.  Oliver Hazard Perry led the Americans to victory in the Battle of Lake Erie in 1813.  However, in 1814, the White House was burned down by the British and the President and his wife were forced to flee.  The inconclusive war ended in 1814 with the Treaty of Ghent, which retained the status quo.  This war fueled the American textile industry and led to the era known as the "Era of Good Feelings".   

        Tension between Mexico and the United States was fueled by the Texans' revolt against Mexico and their establishment of an independent state.  At the same time, the United States was looking toward Northern Mexico, especially areas like California, New Mexico, and Arizona that were sparsely populated.  President James K. Polk ordered General Zachary Taylor to initiate a border conflict with the Mexicans at the Rio Grande River.  When the Mexicans fired upon the Americans, Polk went before Congress to ask for a declaration of war, claiming that "American blood had been spilled on American soil".  American troops invaded Mexico and the Mexicans were utterly routed in every major battle.  The war ended with the Treaty of Guadalupe-Hidalgo in 1848.  Under the treaty, Mexico ceded nearly all of present New Mexico, Utah, Nevada, Arizona, California, Texas, and Colorado.  The war made Zachary Taylor a national hero and helped him win the presidential election.  However, it also opened the slavery issue and further divided the North and South.

        The sectional crisis that had torn the North and South apart came to a head in 1860 with the election of Abraham Lincoln.  The "fire-eaters" of the South feared that the Republican president would interfere with their way of life.  In December 1860, South Carolina seceded from the Union.  It was quickly joined by Alabama, Florida, Georgia, Louisiana, Mississippi, and Texas.  They formed the Confederate States of America and named Jefferson Davis as president.  Confederate forces attacked the Union stronghold of Fort Sumter in April 1861, and this started the Civil War.  Arkansas, North Carolina, Tennessee, and Virginia also seceded and joined the Confederacy.  The first two years of the war were locked in relatively stalemate with Confederate victories like Bull Run and Fredericksburg and Union victories at Antietam and Shiloh.  However, the decisive year was 1863 with the great Union victory at Gettysburg, where Confederate forces under Robert E. Lee were thrown back from Northern soil.  In the West, Ulysses S. Grant and his men captured Vicksburg, Mississippi, and this divided the Confederacy in half.  Grant was named by Lincoln as supreme commander, and for two years he determinedly chased Lee and his men, finally forcing him to surrender at Appomattox Court House on April 9, 1865.  Five days later, President Lincoln was assassinated by John Wilkes Booth.  The era of Radical Construction had begun.

        The war originated in Cuba's struggle for independence. The yellow journalism of newspapers of William Randolph Hearst and Joseph Pulitzer fanned U.S. sympathy for the rebels, which increased after the unexplained destruction of the Maine.  The American populace was led to think that the Spanish had sabotaged the Maine and this heightened its demand for war with Spain.  President McKinley, under pressure from the public, declared war on Spain.  The Americans easily defeated the Spanish, and Theodore Roosevelt and his Rough Riders' heroic charge up San Juan Hill helped to promote Roosevelt's reputation.  In the Treaty of Paris (December 10, 1898), Spain renounced all claim to Cuba and ceded Guam, Puerto Rico, and the Philippines to the U.S., marking the U.S.'s emergence as a world power.

        The U.S. involvement in World War I was late but it was enough to turn the tide against Germany and her allies.  The Great War had already been raging in Europe since 1914 and in 1917, there was still no end in sight.  In 1917, several key events set up the stage for the U.S. entry into the war.  Two years earlier, the Lusitania was sunk by German U-Boats adhering to their unrestricted submarine warfare doctrine.  President Woodrow Wilson protested the Germans' actions, and they agreed to end unrestricted submarine warfare in the Sussex Pledge.  However, by 1917, the Germans were clearly desperate, and they resumed unrestricted submarine warfare in an attempt to cut off British supplies.  At the same time, the British intercepted the Zimmerman telegram and gave it to the United States.  In the document, Zimmerman, the German foreign minister, requested Mexico to enter the war in an exchange for help in recapturing their Southwest territories.  When the telegram was published, it infuriated the American public, and President Wilson went before Congress to ask for a declaration of war to make the world "safe for democracy".  The American soldiers, or "doughboys", were inexperienced but courageous and helped the French and British repel the final German offensive.  The war ended on November 11, 1918, with an armistice by both sides.  During the Paris Peace Conference, the Germans were utterly humiliated and subjected to harsh punishment by the Allies.  The harsh conditions imposed on the Germans helped to fuel their bitter resentment and eventually led to the Second World War.  The United States retreated into isolationism after the war. 

        On December 7, 1941, the United States was plunged into the most horrific and disastrous war of human history with the Japanese attack on Pearl Harbor.  The next day, President Roosevelt gave his famous speech asking for a declaration of war against Japan.  The U.S. also entered the war against Japan's allies, Germany and Italy.  Earlier in 1941, President Roosevelt and Prime Minister Winston Churchill had already secretly met and issued the Atlantic Charter, which denounced tyranny and aggression and promoted a postwar peace plan.  The Allies took the initiative from the Axis around 1943, with the German defeat at Stalingrad and the Japanese now on the defensive after the disastrous battle of Midway Island.  On June 6, 1944, known as D-Day, U.S. and British forces under the supreme command of General Dwight D. Eisenhower, invaded Normandy, France, in the largest amphibious landing in history.  The Germans were quickly pushed back and surrendered unconditionally on May 8, 1945.  The Japanese, however, fought tenaciously and stubbornly in defense of their territories.  The Americans were able to capture the islands of Iwo Jima and Okinawa only after bloody fighting and sustaining heavy casualties.  This prompted Roosevelt's successor (he died in April 1945), Harry S. Truman, to use the atomic bomb on Japan.  The atomic bomb was dropped on Hiroshima and Nagasaki and managed to convince the Japanese that further fighting was futile.  The Japanese formally surrendered on September 2, 1945.  The Allies divided Germany into zones of British, French, U.S., and Soviet occupation.  Japan was placed under temporary U.S. administration, with the leadership of General Douglas McArthur.  The United Nations was established to maintain peace and preserve the balance of power.  The rivalry between the two superpowers, U.S. and Soviet Union, at the end of the war precipitated into the Cold War. 

          The Cold War came to a hot confrontation in Korea.  Korea had been divided into a North Communist Korea and a South Korean republic at the end of World War II.  In 1950, North Korea, with Soviet approval, invaded the South and overran Seoul.  The United States asked the United Nations to send troops to aid South Korea.  The Soviet Union's ambassador was out on a boycott because of the refusal to seat the People's Republic of China.  As a result, the United States sent its forces under the U.N. banner to the South's aid.  However, the U.N. forces were pushed back to the Pusan Perimeter.  General McArthur staged an amphibious landing at Inchon that took the North Koreans by surprise and sent them sprawling across the 38th parallel.  The U.N. forces continued to push into the North, captured Pyongyang, and were at the Yalu River.  The Chinese felt threatened by this presence of troops and streamed across and pushed back the Americans and their allies back across the 38th parallel.  McArthur wanted to use nuclear weapons on the Chinese but was overruled by President Truman, who feared of starting another world war.  When McArthur took his case to the American public, he was fired for insubordination.  The Communist allies were slowly pushed back to the 38th parallel and the war resulted in a stalemate for 2 years.  In 1953, an armistice was signed and the war was unofficially over. 

        The U.S. involvement in Vietnam began in 1954 with the French defeat by the Vietminh at Dienbienphu.  The Geneva Accords of 1954 divided Vietnam into a communist North and democratic South, similar to the situation in Korea.  Shortly afterward, North established the National Liberation Front in an attempt to unify the country under their rule and sent Vietcong guerillas to infiltrate the South.  President Kennedy sent 16,000 advisers to Vietnam to train the South Vietnamese Army.  The president of South Vietnam was Ngo Dinh Diem but he was repressive and unpopular and was assassinated in a coup.  Kennedy was also assassinated in November 1963, and his successor, Lyndon B. Johnson, vastly expanded the American influence in Vietnam.  In 1964, Johnson claimed that North Vietnamese patrol boats had attacked American vessels in the Golf of Tonkin.  Accordingly, Congress passed the Golf of Tonkin Resolution which authorized Pres. Lyndon B. Johnson to use "all necessary measures" to repel armed attacks against U.S. forces in Vietnam.  In 1965, the United States sent its first combat troops to Vietnam.  At the height of U.S. involvement, there were more than half a million U.S. military personnel in Vietnam.  The Tet Offensive in 1968 was considered a military victory by the United States but was a political defeat because it dramatically turned public opinion against the war.  Richard Nixon was able to win the 1968 presidential election because he pledged to end the war "with honor".  In 1973, the Paris Peace Accords called for a cease-fire on both sides and the withdrawal of all American troops from Vietnam.  Thus, the U.S. involvement in Vietnam ended, but more than 58,000 Americans had died