The title is accurate; the film really is in color, not "colorized." It's also a little on the candid side. I suppose sixty years and a rearranged geopolitical milieu makes for greater objectivity.
The war had a curious beginning in 1950. At the end of World War II, the Japanese surrendered to whatever Allied forces were at hand. They happened to be communists above the 38th parallel and Sigmun Rhee below it. Leaders of both the North and the South were anxious to invade one another, both being dictators, and establish hegemony over the Korean peninsula. Truman refused to arm Rhee, knowing what he would do if given the chance. Stalin made the mistake of arming the North, with predictable results.
The war lasted three years and killed or wounded three million people, including civilians. It seesawed back and forth and ended in a stalemate more or less where it began. Both sides signed a truce. There is still no peace treaty, and there are occasional violent incidents at the much-guarded border.
There is a better, lengthier, more detailed three-disc description of the Korean War available. I'd cite it here but I can't find a reference to it, though I've reviewed it.
I'm compelled by my own background in behavioral science to look for a comprehensive approach to the description and interpretation of events. At this point in the game, the last thing I want to hear is a flag-waving cheer for good guys fighting the bad guys. This documentary is uneven in that respect but still gets a pretty good score.
The placid narration doesn't dwell on it but America's first response to the invasion by the North was to send Task Force Smith over from Japan. These were mostly inexperience garrison troops expecting that a show of American force would cause the North Koreans to quail and go back home. They were in for a surprise because none had ever seen a bazooka round bounce harmlessly off the hull of a Russian-made T-34, the best medium tank of the war.
The narration does give MacArthur credit for taking risks that paid off but it slights his difference with President Truman. The film tells us that "Big Mac" wanted to blockade Chinese ports and bomb the Chinese mainland, which alone might have precipitated World War III. It doesn't tell us that some of his proposals were frankly nuts. MacArthur also suggested using nuclear bombs to establish a "buffer zone" north of the Chinese border. And he threatened to "unleash" the corrupt Chiang Kai-Sheck from Taiwan and let him attack the Chinese mainland, where Chiang had just lost the war against the communists.
At any rate, Korea is no longer the hot spot it was, and whatever the political ups and downs of the North and the South, the South won. It's easy to Google a night-time photo of the peninsula. The South is aglow with lights -- bright spots for cities and towns and highway beads connecting all the communities. North of the 38th parallel, everything is black except for a few dim lights representing the larger cities.