The Cold War: Tensions, Proxy Wars, and Destruction

Following the defeat of Nazi Germany and the Empire of Japan in late 1945, the world entered a new era, marked by two superpowers standing off against each other. These two massive empires—one capitalist, the other communist—had once been close allies in the anti-fascist war. However, the stark differences in their governing structures and beliefs did nothing to alleviate the already near-breaking tension.

The first major challenge to the fragile "friendship" between the U.S. and USSR arose with the division of territories in Italy, Germany, and Japan. Joseph Stalin, the USSR's widely feared leader, had, despite leading his country through the period of the Great Purge, a deadly man-made famine, and committing wide-scale atrocities, proven to be an able military leader by leading the Soviet Union's armored forces to storm Berlin, the capital and largest city of Nazi Germany. Due to his efforts, he demanded control of all Eastern Europe, including Germany, Bulgaria, Czechoslovakia, Hungary, Poland, Romania, Yugoslavia, and Albania. These countries will be referred to as the "Eastern Bloc" for the rest of this passage. Stalin's plan to divide Europe into two halves faced fierce opposition from Harry Truman and Winston Churchill, leaders of the U.S. and U.K. In the end, however, fearing the USSR's elite armored divisions stationed across Eastern Europe, they conceded on one condition: the Soviets would retain only half of Germany.

Fig. 1: The Eastern and Western blocs in 1950
One country split into two, with different government systems but the same cultural heritage and symbolic ties, is a terrible outcome. Yet this pattern would continue to emerge throughout the Cold War era.

Following the split of Germany came the separation of Korea. As a former Japanese colony, Korea, like many other nations and colonies, was split into two by the two major world doctrines. In the north, the USSR-supported Democratic People's Republic of Korea was established with Kim Il Sung as its leader. Commonly referred to as North Korea, it remains a communist dictatorship to this day. In the south, a capitalist republic was established with Syngman Rhee as its "president," though in reality, it was still a dictatorship. The two sides agreed on a temporary border along the 38th parallel, which almost precisely divided the peninsula in half.

The joint military occupation of the Korean Peninsula remained relatively peaceful for about five years until Kim Il Sung, in an attempt to reunite the peninsula (with him in charge, of course), began to build up his army, assembling seven infantry divisions along with one armored division, totaling around one hundred thousand men, all equipped with Soviet weapons. The infantry equipment supplied to North Korea varied, including the dreaded Mosin-Nagant bolt-action rifle, the PPSH-41/43 submachine guns, and the PM-1910/30 heavy machine guns, all produced during World War II but kept in mint condition. Also supplied to North Korea was the T-34/57 medium tank, the reliable armored vehicle that served the Soviet Union throughout World War II.

Feeling confident with these newly supplied weapons, Kim Il Sung launched a full-scale invasion campaign on South Korea on June 25, 1950, dividing his army of about 100,000 men into three separate army groups. The advance was rapid, as the Korean People's Army (KPA) captured Inchon on June 19, followed by Seoul on June 28. South Korean government officials and property were forced to retreat to the southernmost city of Pusan.

Fig. 2: Maximum territorial control of North Korea in September 1950
As the South Korean Army struggled on the battlefield, the United States decided to take action to defend this strategically important ally in Asia by manipulating the United Nations Security Council to reach a decision to create a United Nations Command Army (UNC), consisting of 11 nations, to support South Korea. The UNC marched toward the Pusan Perimeter from all over the world. Under the leadership of U.S. General Walton Walker, the combined forces of the United States and South Korea built up a defense along the Naktong River, successfully stopping the North Korean advance. However, the South only retained about 1/10th of its original territory.

North Korea, however, was in trouble. The Korean People's Army had limited manpower and weapons, and although they controlled most of South Korea's territory, the UNC was already arriving in mass quantities into the Pusan Perimeter, totaling 144,000 troops combined with the South Korean Army, compared to the DPRK's 90,000 troops.

Breaking out of the Pusan Perimeter was now just a matter of time. In his Tokyo headquarters, General Douglas MacArthur, commander of all U.S. troops stationed in Asia, laid out a map of the Korean Peninsula, took a few puffs from his pipe, and pointed at Inchon, a strategic port near the 37th parallel.

"We will land there, and that's final," he said.

MacArthur's decision was extremely shrewd. Landing at Inchon not only provided an opportunity to split the KPA in half, encircling about 40,000 troops, but also allowed South Korea to advance north almost as quickly as the KPA retreated. After a successful landing of about 12,000 troops at Inchon, MacArthur, filled with emotion and joy, ordered the combined American forces to swiftly retake the rest of South Korea, as the breakout from the Pusan Perimeter was also launched the following day.

Fig. 3: The landing at Inchon
The KPA, seeing the swift movements of the mechanized UNC forces, quickly took action to secure their base. Retreating from the southern half of the peninsula, the KPA established defenses along the 38th parallel. However, under heavy firepower and with the UNC's air and naval superiority, the KPA's defenses crumbled.

Both South Korean and American troops advanced at lightning speed into North Korean territory. However, it was the South Korean troops that crossed the 38th parallel first, due to a clever move by President Truman aimed at diverting international responsibility for interfering in and supporting South Korea in what was now being termed a "civil war."

As the UNC advanced closer and closer to the Yalu River, China could no longer stand idly by. At the start of the war, Mao Zedong, Chairman of the People's Republic of China (PRC), and his military advisers had warned Kim Il Sung multiple times that once the United States entered the war, his forces would crumble rapidly. However, doubting the likelihood of the United States entering the war due to the Soviet Union's threat, Kim proceeded with his plans. Now, with his forces and territory collapsing and even his capital, Pyongyang, having fallen, he sought aid and alliance from the USSR.

There was no response. Stalin, citing a muddled reason that he feared an all-out nuclear war, gave silent permission to Washington to continue its operations. With no help from Moscow, Kim had only one more ally to rely on.

China. Unlike the USSR, China took decisive action. Viewing North Korea as a buffer against South Korea and U.S.-controlled Japan, China was prepared to save North Korea at all costs. Four Chinese armies assembled on the northern bank of the Yalu River, ready to strike into North Korea and turn the tide of the war.