How effectively did the USA contain the spread of communism?

Who controlled Korea between 1910 and 1945?

Japan controlled Korea during this entire period.

What happened to Japanese forces in Korea at the end of WWII in 1945?

Japanese troops in the north surrendered to the USSR; those in the south surrendered to the US

What geographical line was used to divide Korea after WWII?

The 38th Parallel separated the Soviet-occupied north from the US-occupied south.

What did the UNO call for in Korea in 1947?

Free, nationwide elections to create a democratic government for the entire country.

When were UNO-supervised elections held in Korea, and where?

In 1948, elections were held only in the south under UNO supervision.

When were UNO-supervised elections held in Korea, and where?

In 1948, elections were held only in the south under UNO supervision.

What state was formed in South Korea in 1948?

The Republic of Korea, led by Syngman Rhee, with its capital in Seoul.

What state was formed in North Korea in 1948?

The Democratic People’s Republic of Korea, led by Kim Il-Sung, with its capital in Pyongyang.

How did both Korean governments view themselves after 1948?

Both claimed to be the legitimate government of all Korea.

What was Kim Il-Sung’s main motive for invading South Korea in June 1950?

In June 1950, He wanted to reunify Korea under communist rule.

Why did Kim believe an invasion would succeed? (general)

He thought he had strong military backing, superior forces, and little risk of American intervention.

Which major communist leaders supported Kim Il-Sung’s plan to invade?

Stalin (USSR) and Mao Zedong (China).

How did North Korea’s military compare to South Korea’s by 1950?

North Korea had a far stronger military, armed with Soviet tanks, artillery, and aircraft.

Why did Kim think the USA would not intervene in Korea?

Because China was now communist, the USSR had the atomic bomb (since 1949), and Korea didn’t seem a US priority.

Which American statements encouraged Kim to believe Korea was unimportant to US defence?

Leading American politicians publicly suggested Korea lay outside the USA’s key defence perimeter.

How did the United Nations become involved in the Korean War?

The UN became involved after North Korea invaded South Korea on June 25, 1950. The Security Council immediately passed Resolution 82, calling for a ceasefire and withdrawal. This was possible because the Soviet Union was boycotting the Council and could not veto. When North Korea ignored the resolution, the UN passed Resolutions 83 and 84, which authorized military assistance and placed all forces under a unified US command.

What were the key UN resolutions at the start of the Korean War?

The key resolutions were UN Security Council Resolution 82 (June 25), which demanded an end to hostilities; Resolution 83 (June 27), which recommended military aid to South Korea; and Resolution 84 (July 7), which placed the multinational force under US command.

Why was the United States so determined to intervene in Korea?

The US was committed to its containment policy to stop communist expansion. It viewed the invasion as a Soviet-backed test of resolve. Strategically, the US feared a domino effect that could lead to the fall of Formosa (Taiwan) and threaten Japan, its key ally in Asia. A firm response was seen as necessary to prevent a major shift in the global balance of power.

How did the United Nations become involved in the Korean War?

The UN became involved after North Korea invaded South Korea on June 25, 1950. The Security Council immediately passed Resolution 82, calling for a ceasefire and withdrawal. This was possible because the Soviet Union was boycotting the Council and could not veto. When North Korea ignored the resolution, the UN passed Resolutions 83 and 84, which authorized military assistance and placed all forces under a unified US command.

What were the key UN resolutions at the start of the Korean War?

The key resolutions were UN Security Council Resolution 82 (June 25), which demanded an end to hostilities; Resolution 83 (June 27), which recommended military aid to South Korea; and Resolution 84 (July 7), which placed the multinational force under US command.

Why was the United States so determined to intervene in Korea?

The US was committed to its containment policy to stop communist expansion. It viewed the invasion as a Soviet-backed test of resolve. Strategically, the US feared a domino effect that could lead to the fall of Formosa (Taiwan) and threaten Japan, its key ally in Asia. A firm response was seen as necessary to prevent a major shift in the global balance of power.

What was the nature of the UN military effort in Korea?

The UN force was overwhelmingly American. US General Douglas MacArthur was in command. American troops constituted half of the ground forces, over 90% of the air forces, and 85% of the naval forces. While 15 other nations contributed, the operation was largely directed and supplied by the United States.

What critical circumstance allowed the UN Security Council to act on Korea without a Soviet veto?

The Soviet representative was boycotting the Security Council to protest the exclusion of communist China from the United Nations. This absence meant the USSR could not use its veto power to block the resolutions authorizing intervention in Korea.

What were the six main phases of the Korean War?

Phase 1 (June-Sept 1950): North Korean success, overrunning most of South Korea and confining UN forces to the Pusan Perimeter. Phase 2 (Sept-Oct 1950): UN success with a counterattack, including the Inchon landing, driving North Korea back past the 38th parallel. Phase 3 (Oct-Nov 1950): UN push north to reunify Korea, reaching the Yalu River. Phase 4 (Nov 1950-Jan 1951): Massive Chinese intervention drives UN forces back south, recapturing Seoul. Phase 5 (Jan-July 1951): UN counterattack pushes back to the 38th parallel; MacArthur is dismissed. Phase 6 (July 1951-July 1953): Stalemate and lengthy negotiations lead to an armistice, leaving Korea divided.

What were the results of the Korean War for the UN?

The UN proved more effective than the League by using force. But it failed to unify Korea. The war caused massive casualties (4 million Koreans) and was only possible due to the Soviet boycott over China's UN seat.

Why did the US have influence in Cuba before the 1950s?

After 1898, the US controlled Cuban politics and economy. It forced Cuba to sell raw materials cheaply, buy US goods, and US businesses owned much of the land and industry. The US also had the Guantanamo Bay naval base.

What caused Cuban discontent with the US by the 1950s?

Cubans resented 50 years of US economic domination and political control. Governments had to follow US policies, and corruption was rampant. This created widespread anti-American sentiment.

How did Cuba change under Castro?

Castro nationalized industries, redistributed land, and ended segregation. He provided free education and healthcare, expelled the Mafia, and closed casinos. He gained popular support but became repressive, jailing critics and canceling elections. He shifted Cuba's alliance from the US to the USSR.

How did the US react to Castro's revolution?

The US imposed economic sanctions, cutting off trade and sugar purchases. It also authorized a secret CIA plan to overthrow Castro, which led to the failed Bay of Pigs invasion.

What was the Bay of Pigs plan?

A 1961 CIA operation using 1,400 Cuban exiles. Planes would bomb Cuban airbases, then troops would land at the Bay of Pigs to spark an uprising and march on Havana to overthrow Castro.

Why did the Bay of Pigs fail?

Poor secrecy meant Castro knew about it. The air strikes failed to destroy Cuba's air force. US involvement was exposed, and Cuban forces were ready, defeating the invasion quickly.

Why did the Soviet Union place nuclear missiles in Cuba?

There were political and military reasons. Politically, Khrushchev wanted to appear strong against the US and protect his ally Castro from another invasion after the Bay of Pigs. Militarily, Cuba was only 90 miles from the US, providing a close base for Soviet missiles to counter the US advantage from its own missiles in Turkey.

What was the timeline leading to the Cuban Missile Crisis?

In April 1962, the US placed missiles in Turkey. In July, the US imposed a full trade embargo on Cuba. Soviet advisors then told Castro the US was planning another invasion. Secret shipments of Soviet missiles to Cuba began that summer. On October 15, 1962, US U-2 spy planes photographed the missile sites in Cuba, beginning the crisis.

How was the Cuban Missile Crisis resolved?

A deal was reached. The Soviet Union agreed to dismantle and remove its missiles from Cuba. In return, the US publicly pledged not to invade Cuba. In a secret part of the deal, the US also agreed to remove its own nuclear missiles from Turkey.

What were the long-term effects of the Cuban Missile Crisis?

It was seen as a US victory, boosting American prestige and Kennedy's image. However, it solidified Cuba's status as a communist satellite state dependent on the USSR. Some US military leaders felt Kennedy had been too soft. The crisis led to the establishment of a direct communication hotline between Washington and Moscow to prevent future miscalculations.

What was the Cuban Missile Crisis?

The Cuban Missile Crisis was a 13-day confrontation in October 1962 between the United States and the Soviet Union over the Soviet deployment of nuclear missiles in Cuba, just 90 miles from the U.S. coast. It was the closest the Cold War came to escalating into a full-scale nuclear war.

What was the initial outcome of the NK invasion?

North Korean forces overran most of the South, pushing UN/ROK troops back to the Pusan Perimeter.

What was the significance of the Inchon Landing (Sept 1950)?

General MacArthur’s amphibious attack cut NK supply lines, forcing a rapid North Korean retreat.

Why did China enter the war in October 1950?

UN/US forces crossed into North Korea and neared the Yalu River; China feared invasion and US presence on its border.

What did Chinese intervention achieve?

It pushed UN forces back into South Korea, recapturing Seoul and stabilising the front around the 38th Parallel.

Why was MacArthur dismissed in 1951?

He publicly criticised Truman and wanted to expand the war into China; Truman insisted on limited war to avoid WWIII.

What characterised the later stages of the war (1951–53)?

Stalemate along the 38th Parallel, heavy trench warfare, and long armistice negotiations.

How long did the Korean war last?

25 June 1950 to 27 July 1953.

Why did the war end in an armistice?

Exhaustion on all sides, Stalin’s death reducing Soviet support, and agreement on POW exchanges.

How did the U.S. respond when it discovered the missiles?

Why did the United States become involved in Vietnam?

The US became involved to prevent the spread of communism, guided by the "domino theory." After France's defeat and withdrawal in 1954, Vietnam was temporarily split. The US backed the anti-communist South Vietnamese government because it feared a unified, communist Vietnam would cause other Southeast Asian countries to fall to communism. The US opposed the planned 1956 reunification elections, knowing communist leader Ho Chi Minh would likely win.

What was the Domino Theory?

The Domino Theory, articulated by President Eisenhower, was the belief that if one country in a region fell to communism, neighboring countries would also fall in quick succession, like a row of dominoes. This fear drove US policy to contain communism in Southeast Asia, starting with Vietnam.

What was the Geneva Peace Accord of 1954?

he Geneva Peace Accord ended French colonial rule in Indochina. It temporarily partitioned Vietnam at the 17th parallel into communist North Vietnam (led by Ho Chi Minh) and anti-communist South Vietnam. It called for nationwide elections in 1956 to reunify the country, but these elections were never held, largely due to US and South Vietnamese opposition.

How did US involvement escalate under President Eisenhower?

Eisenhower initially sent aid and military advisors to support the French. After their defeat, he provided extensive military and economic aid to the new South Vietnamese government and increased the number of US military advisors there to 900. He viewed Vietnam as a crucial test of the domino theory and containment.

How did US involvement escalate under President Kennedy?

Kennedy significantly increased military aid and advisors. He raised the number of US military advisors from 900 to 12,000, sent 300 helicopters, and funded an expansion of the South Vietnamese army. He also initiated the failed "Strategic Hamlet Program" to isolate peasants from the Vietcong. His actions were influenced by the desire to appear strong after foreign policy setbacks like the Bay of Pigs.

What was the Strategic Hamlet Program and why did it fail?

It was a Kennedy-era policy to move South Vietnamese peasants into fortified villages to protect them from Vietcong influence. It failed because peasants were forcibly relocated, resisted leaving their ancestral lands, and found it impractical for farming. The program increased resentment against the South Vietnamese government.

What internal crisis weakened the South Vietnamese government under Diem?

The Diem regime faced a major crisis in 1963 due to its repression of Buddhists. This culminated in Buddhist monks publicly setting themselves on fire in protest. The government's brutal response and Diem's loss of control led to a US-backed military coup in November 1963, in which Diem was assassinated.

What was the Gulf of Tonkin Incident?

In August 1964, it was reported that North Vietnamese gunboats attacked two US destroyers in international waters. This incident led the US Congress to pass the Gulf of Tonkin Resolution, which granted President Johnson the authority to use military force in Southeast Asia without a formal declaration of war, marking a major escalation of direct US combat involvement.

What was the Tet Offensive and why was it a turning point?

The Tet Offensive was a massive surprise attack launched by North Vietnamese and Vietcong forces in January 1968 against nearly 30 US targets and dozens of South Vietnamese cities. Militarily, it was a defeat for the communists, but its scale and the intense media coverage shocked the American public. It shattered the belief that the US was winning the war, causing a dramatic drop in public support and convincing many that the war was unwinnable.

What was the My Lai Massacre?

In March 1968, US Army troops killed hundreds of unarmed Vietnamese civilians, including women and children, in the village of My Lai. The massacre, which was covered up for over a year, became public in 1969 and further eroded American moral authority and domestic support for the war, fueling anti-war sentiment.

What was "Vietnamization" under President Nixon?

Vietnamization was Nixon's policy to gradually withdraw US troops from Vietnam while increasing the training and arming of the South Vietnamese Army (ARVN) to take over the bulk of the fighting. It aimed to achieve "peace with honor" by allowing the US to exit the war while leaving South Vietnam capable of defending itself.

How did Nixon try to end the war, and what was the final outcome?

Nixon pursued Vietnamization and secret negotiations. He also escalated the war secretly by bombing communist bases in Cambodia in 1970 and later sending ground troops there, which sparked massive anti-war protests at home (like at Kent State University). A peace treaty was finally signed in Paris in 1973, leading to a full US withdrawal. Fighting resumed, and without US support, South Vietnam fell to a North Vietnamese invasion in 1975, unifying the country under communist rule.

Who were the Viet Minh?

A nationalist-communist resistance movement founded by Ho Chi Minh in 1941 to fight Japanese occupation, later fighting French colonial rule.

What was the main goal of the Viet Minh?

To gain Vietnamese independence from foreign powers (Japan, then France).

When did the Viet Minh become a major force?

During WWII against Japan and after 1945 in the First Indochina War against France, leading to the 1954 victory at Dien Bien Phu.

What part of Vietnam did the Viet Minh control after 1954?

They formed the communist government of North Vietnam under Ho Chi Minh.

Who were the Viet Cong (VC)?

: A communist guerrilla force in South Vietnam that fought the South Vietnamese government and the United States.

When were the Viet Cong formed?

Around 1960, as the armed wing of the National Liberation Front (NLF).

What was the Viet Cong’s goal?

To overthrow the US-backed South Vietnamese government and unify Vietnam under communist rule.

How did the Viet Cong fight?

Using guerrilla tactics — ambushes, tunnels, sabotage, and blending with civilians.

What was the relationship between the Viet Cong and North Vietnam?

The VC were supported, supplied, and directed by North Vietnam but operated mainly inside the South.

What was the relationship between the Viet Minh and the Viet Cong?

The Viet Minh were the original communist-led independence movement that defeated the French and established communist North Vietnam in 1954. The Viet Cong were later created (around 1960) as the communist guerrilla movement in South Vietnam. Many Viet Cong leaders were ex-Viet Minh, and North Vietnam (run by the former Viet Minh) organised, supplied, trained, and directed the Viet Cong during the Vietnam War.

Why did Kennedy go ahead with the Bay of Pigs invasion even though he was unsure about it?

The plan was inherited from Eisenhower, already prepared by the CIA, and Kennedy feared cancelling it would show weakness against communism early in his presidency.

Why did Kennedy blame others (like the CIA) for the Bay of Pigs failure?

The CIA had assured him it would spark an anti-Castro uprising and succeed easily. Their intelligence was wrong, the operation was poorly planned, and they underestimated Castro’s strength—allowing Kennedy to distance himself from the disaster.

What triggered the Cuban Missile Crisis?

US spy planes discovered Soviet nuclear missile bases being built on Cuba in October 1962.

Why did Kennedy choose a naval blockade instead of an airstrike or invasion?

A blockade avoided immediate war, still pressured the USSR, gave time to negotiate, and reduced the risk of nuclear retaliation. It showed firmness without provoking WWIII.

How did early US presidents escalate involvement in Vietnam before Johnson?

Truman and Eisenhower funded the French; Eisenhower and Kennedy increased advisers and equipment to South Vietnam but avoided major troop commitments.

Why was Johnson the first to send large-scale US ground forces?

After the reported attacks on US destroyers in the Gulf of Tonkin (1964), Johnson received the Tonkin Resolution, giving him authority to massively escalate US military involvement.

How did the Tet Offensive contribute to US withdrawal?

It shocked Americans by proving the Viet Cong could strike anywhere, undermining claims the war was being won and turning public opinion against continuing the conflict.

How did US casualties influence withdrawal?

Rising deaths and injured soldiers made the war increasingly unpopular at home, with families and the public demanding an end to the conflict.

Why did media coverage push the USA toward withdrawal?

Graphic TV reports, images of civilian casualties, and events like My Lai caused widespread anger and made people doubt the war’s morality and purpose.

How did anti-war protests affect US policy?

Huge demonstrations, student protests, and political pressure forced leaders to rethink strategy and seek a way out of the war.

What role did the cost of the war play in withdrawal?

The war was draining billions of dollars, damaging the US economy, and reducing funding for domestic programs—making continued fighting unsustainable.

How did relations with China and the USSR affect withdrawal?

Nixon wanted better relations with both superpowers; ending the Vietnam conflict helped reduce Cold War tension and strengthen diplomacy.

What impact did the Laos and Cambodia bombings have on withdrawal?

They expanded the war and caused outrage at home, increasing pressure on Nixon to speed up US troop withdrawals.

Why was America ultimately unable to win in Vietnam?

The Viet Cong’s guerrilla tactics, knowledge of terrain, local support, and North Vietnamese determination made victory extremely difficult for US forces.