MacArthur was an expert in editing/adjusting information from the theater of his command for his own benefit and image. General Dwight Eisenhower
thought a younger, more with-it commander was necessary as the early stages of the Korean War unfolded. Eisenhower and others saw potential trouble ahead with MacArthur, a general that felt that he was basically "untouchable". MacArthur believed that he was on a holy mission against evil Communists, and was at the summit of one of the most glorious military careers in U.S. History.
MacArthur's mother, Pinky, actually moved nearby to West Point during MacArthur's time there, and constantly interfered/dominated, even with the women her son was seeing. Pinky was also a pain-in-the-butt advocate for her son's advancement. At age 38, MacArthur became the youngest division commander in the US Army, but he was already paranoid about Army HQ not seeing the magic that was him . . . MacArthur badly wanted the Medal of Honor, which his father was awarded at age 18 during the Civil War.
In 1930, MacArthur became the Chief of Staff for the Army after a good deal of wheeling and dealing on his part, as well as Pinky's. MacArthur was a complete narcissist as well as brilliant, talented petulant, manipulative, theatrical, political, and given to wild mood swings. MacArthur's favorite pronoun was the 1st Person. MacArthur didn't share glory with subordinate commanders, and made sure that Army HQ gave him full credit for victories that occurred under his overall command.
MacArthur once commented to another general that he couldn't understand why Ike (Eisenhower) gave credit and publicity to Generals Omar Bradley and George Patton during World War II. Like other narcissists, MacArthur idealized his life and his role in it, and if he made a mistake, he refused to admit it and take responsibility. Blame was directed to rivals suspected of targeting MacArthur for a downfall: an example - the grossly unprepared US troops that first arrived at South Korea under his command was the fault of the Pentagon.
when he wasn't posing. By 1950 (like George Washington), MacArthur needed glasses, but he wouldn't let anyone know that he needed them.
All that being said, MacArthur took an under-strength US Army in the Pacific in 1942 with little air and naval support, and charted a course of great military strategic originality. MacArthur rarely attacked Japan where they were strong, instead striking Japan on smaller islands where their defenses were weaker. MacArthur understood that the days of large frontal assaults (as in WW I) were over. MacArthur used air power to great effect, taking island that would be strategically significant then-or-later.
No general in WW II used airpower better than MacArthur; he seemed to have a sixth sense of what Japan would do, and when they would do it. As a result of his successes using airpower, MacArthur had an exaggerated sens of the usefulness/impact of air strikes, of which he would pay a steep dearly during the Korean War.
Victorian mind simply couldn't see (or comprehend) the revolution taking place against colonialism, particularly in China . . . the China that MacArthur felt he knew so well no longer existed.
During August 1950, the tide at Pusan began to turn. The US position grew stronger, and the North Korean army was figuratively/literally running out of gas, as well as men and ammunition. And that was the moment for which General MacArthur had been waiting; the general had been waiting for a chance for an amphibious assault behind the North Korean line.
This time, North Korea would be unprepared, since the vast majority of their army was well past the 38th Parallel. MacArthur would then move East-and-North to entrap the North Korean army. MacArthur even had a location selected, Inchon, the great natural port on the west coast of South Korea. To MacArthur, it was a no-brainer: North Korea would either have to pullout or surrender.
But MacArthur was adamant, seeing Inchon as the way to avoid a "meatgrinder" of a war out of Pusan. On 23 August 1950, the critical meeting occurred concerning Inchon, where two members of the Joint Chiefs tried to talk MacArthur out of his plan . . . but MacArthur got his way. In September 1950, US Marines landed on Wolni, a small island guarding the mouth of Inchon harbor; 13,000 Marines poured on to the island and faced minimal resistance. For those US (technically United Nations) forces, it was a race to Seoul to trap the North Korean army. Inchon was MacArthur's finest hour; before Inchon, MacArthur was "untouchable", but afterwards, he was a deity. On 26 September 1950, Seoul was taken from North Korea, eleven days after MacArthur's forces landed at Inchon.
The problem, however, was that no one in the government or military had defined any objective after MacArthur crossed the 38th Parallel, and MacArthur (and most of D.C.) had no idea of the strength of Mao Tse-Tung's forces in China. On the
7th of October 1950, US troops crossed the 38th Parallel, and the next day Mao ordered a massive mobilization towards the Yalu River, the border between North Korea and Manchuria. Finally, Truman was getting nervous, registering signals/warnings from Peking (now Beijing), and also, Truman believed that it was very likely that MacArthur was overextending his forces in his pursuit of the enemy in North Korea.
mid-October 1950. Truman wasn't looking forward to dealing with MacArthur, who, like almost all egomaniacal narcissists, strutted while sitting down. Truman's poll numbers were very low, and Truman hoped to bask at least a little in the afterglow of Inchon. Truman had ordered MacArthur to leave his entourage behind; Truman wanted the White House press corps to have a monopoly covering the meeting.
MacArthur went to greet Truman at the President's plane (Truman had serious doubts that MacArthur would do so), and the meeting was basically cordial, but both powerful men were wary of each other. MacArthur belittled the possibility of Chinese intervention, claiming that only 50k to 60k Chinese soldiers at most would cross the Yalu River. MacArthur had spent no time studying Mao's successful tactics against Chiang Kai-Shek's superior forces that resulted in Mao's Communist forces taking over China in 1949. MacArthur still believed that China had a weak army, just as in feudal times.
MacArthur was at his best before/during Inchon . . . after China's massive invasion across the Yalu River in late-1950, MacArthur would be at his worst.