- In November 1950, US-led forces clashed with Chinese troops for the first time during the Korean War, in bitter fighting around the Chosin Reservoir.
- Chosin Reservoir has remained an iconic battle for the US Marines, even as memory of the war has faded over the past 70 years.
- Now, amid tensions between the US and China, Beijing is casting the battle and the war, which ended in stalemate, as a triumph over America.
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On the night of November 27, 1950, US Marines and Army soldiers suddenly came under intense human-wave attacks by Chinese soldiers on both sides of the Chosin Reservoir.
The Americans, part of a UN force of about 30,000 men, soon found themselves in their first major clash with the Chinese during the war, facing the full weight of about 120,000 Chinese soldiers committed to their destruction.
The attacks, by hundreds of troops at a time and in temperatures as low as -36 degrees, marked the start of a brutal 17-day fight that became one of the Korean War's bloodiest battles and one of the most intense battles in modern history.
A dramatic reversal
The events at Chosin were a complete reversal of the course of the war to that point.
After successfully landing at Inchon, near Seoul, in September, a three-pronged counteroffensive by the US-led UN force liberated South Korea from the invading communists and then pushed north across the 38th parallel to destroy the Kim regime and unify the Korean Peninsula.
A little more than a month after Inchon, UN forces took Pyongyang. They pressed forward, smashing what was left of the Korean People's Army and were quickly approaching the Yalu River - the border between North Korea and China.
Unnerved by this development and worried that a unified Korea could be used as a base to attack China, Chairman Mao Zedong ordered the newly created People's Volunteer Army (PVA) to cross into North Korea to assist their communist comrades.
On October 19, 1950, the PVA (which was previously training for an invasion of Taiwan) crossed the Yalu River. They defeated South Korean and American forces at the Battles of Onjong and Unsan in the northwest before moving into position in the east.
Undeterred by these defeats, and believing the Chinese presence to be small, Gen. Douglas MacArthur, commander of UN forces, launched the "Home-by-Christmas" offensive on November 24, sending his men into a trap.
A push in the northeast
The force responsible for liberating eastern North Korea was X Corps, made up of the 1st Marine Division, the US Army's 7th and 3rd Infantry Divisions, and elements of the South Korean I Corps and British No. 41 Royal Marine Commando.
X Corps captured Wonsan on October 28. A day later, Marines landed farther north at Iwon. By November 2, X Corps had secured Hamhung, North Korea's second-largest city.
X Corps easily handled the limited Chinese resistance it encountered and was ordered to push north to the Chosin Reservoir. The idea was to secure the area before turning west toward Kanggye, the new capital of North Korea. In fact, they were being lured in by the PVA.
Advancing on a single road, the Marines took up position on the western side of the lake, with the Army on the eastern side. The advance was going well until the night of November 27.
'Kill these Marines as you would snakes in your homes'
The Chinese attacks were well-planned and coordinated.
With no air support and limited artillery support, the Chinese moved and attacked mostly at night, limiting the effectiveness of American airstrikes and artillery. They used overwhelming numbers to cut off isolated units and within days surrounded the entire UN force.
Their mission was the complete destruction of all UN forces. A captured Chinese pamphlet said "we will destroy them" and exhorted Chinese troops to "kill these Marines as you would snakes in your homes."
Their attacks were relentless and seemed to occur everywhere. An ambush on a convoy of Royal Marine reinforcements coming from the south left 162 of its troops killed or captured. The remainder were divided, with 400 reaching their objective and 300 retreating.
American aircraft dropped tons of napalm and bombs, killing hundreds of Chinese soldiers, but bad weather hindered their operations, and sub-zero temperatures sometimes froze fuel for both tanks and planes.
American positions routinely ran out of ammunition, and fighting often descended to hand-to-hand combat. Now firmly on the defensive, UN forces had to be resupplied by air.
"You had two enemies that you were fighting. You were fighting the cold weather, and then your enemy, the Chinese and North Koreans," Henry Lucido, a 1st Marine Division veteran, recalled.
'Attacking in another direction'
The Americans continued to hold. "We're surrounded. That simplifies our problem of getting to these people and killing them," Col. Lewis B. "Chesty" Puller, a legend in the Marine Corps, told his men.
But the attacks were too much. On the eastern side of the lake, two US Army battalions faced no less than 21 Chinese battalions. On November 30, MacArthur ordered X Corps to withdraw to Hungnam, a port city south of Hamhung.
The Marines and soldiers had to fight every step of the way. Chinese attacks occurred every night, and daytime hours for the UN forces were divided between moving south and attempting to sleep.
"At the time I was numb, and there were so many deaths that I actually hoped I might get hit and not killed," Rayburn Blair, a Marine, said later.
"I thought I was in Hell." Min Gyeong-sik, a South Korean soldier, recalled. "I thought I was living in Hell."
During the withdrawal, three Chinese divisions repeatedly charged the American forces and were destroyed or rendered ineffective.
A reporter asked the Marine commander, Maj. Gen. Oliver P. Smith, about the decision to retreat, to which he responded, "retreat Hell! We're just attacking in another direction."
UN troops marched south along the same road they used to go north. Materials had to be parachuted in so the troops could repair a bridge blown up by the Chinese and continue the retreat. By December 13, UN forces had reached Hungnam.
At Hungnam, UN forces were protected by US Navy warships and carrier aircraft. Over the next two weeks, 105,000 soldiers and 91,000 civilian refugees were evacuated. The port was then destroyed so that nothing was left for the communist forces.
A stalemate and rallying cry
The Battle of Chosin resulted in slightly more than 17,000 UN casualties, most of them US Marines. That included about 2,500 killed in action, over 5,000 wounded, and almost 8,000 suffering frostbite.
The exact number of Chinese casualties isn't known, but the Marines estimated 25,000 Chinese troops were killed and 12,500 wounded. Other estimates put total Chinese casualties between 19,000 and 60,000.
The war settled into a stalemate, and the fighting ended three years later with an armistice that remains in place today. Over the next 70 years, the war largely faded from memory on both sides. But in China, it's getting renewed attention.
In October, Beijing marked its intervention in what it called "the war to resist US aggression and aid Korea."
"The Korean War shows that the Chinese people must not be provoked. If you make trouble, be prepared to bear the consequences," Xi said.