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US History overview 3: WWII to Vietnam

The video explores key events of the 20th century, starting with the Bolshevik Revolution in 1917, leading to the formation of the Soviet Union. It discusses the rise of Hitler, World War II, the Cold War, and the space race. The video also covers the Korean War, the Cuban Missile Crisis, and the Vietnam War. Created by Sal Khan.

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  • aqualine ultimate style avatar for user Debthoms10
    Do u think it was right for us to drop a nuclear bomb on Japan?
    They bombed us first but we bombed them twice.
    I think the second time was too much.
    (8 votes)
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    • leaf red style avatar for user Jack Davis
      It was a judgement call. We could have defeated japan without the use of the bomb. The price would have been many American lives. The result of dropping the bomb was many more Japanese lives. The bomb also served the purpose of a demonstration of power.
      My personal opinion is that to use such knowledge and ingenuity as a means of mass destruction is a failure on the part of man kind. Perhaps that's wasn't as clear then, but I think it is should be a priority to ensure that act will never happen again. Imagine what we could accomplish if we directed our efforts technologies to improve the lives humans in general and not on warfare.
      (17 votes)
  • primosaur ultimate style avatar for user baladitya2003
    At , there is John F. Kennedy's assassination. Who assassinated him?
    (13 votes)
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    • leafers sapling style avatar for user Jay
      and then someone, I think ruby someone killed Oswald. I mean we could go into the conspiracy theories here of how a group decided to leave no loose ends and decided to kill the assassin of JFK and such other theories, but that is not important right now.
      (5 votes)
  • leaf grey style avatar for user Shlomo Fingerer
    () It seems that people justify the nuclear bombing of civilians in Hiroshima and Nagasaki in the fashion: "The atomic bomb did save lives as Hiroshima is 70,000 casualties and Nagasaki was 40,000 casualties. Together, 110,000 is less than 1,000,000. If the invasion of Japan were to take place, then there would be at least 1,000,000 casualties." to quote -ryan725. What I don't understand is: Why invade if you are worrying about lives? We had the Japanese surrounded and besieged. Doesn't common sense dictate, that if you can starve the enemy into surrender than there is no need to waste lives (OR MONEY!) invading? What was the rush to end the war?
    (13 votes)
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    • leaf green style avatar for user LMSBTC
      Just to start out the Japanese were clearly not willing to surrender or even make concessions on the gains they had achieved during their conquest in East Asia, and if the U.S. was forced to leave the region there was no way to assure that Japan would not retake all of the ground gained by the Americans. The autocratic regime there was very good at keeping their populace in the mood to fight on, (they had women training in schoolyards with bamboo sticks toward the end of the war) while the western belligerents had major problems with weariness and even defeatism (many American citizens openly questioned if the war was winnable or even justifiable, and a major political faction in the U.S. was still against going to war in the first place). So the idea that japan had lost the war entirely (although they certainly lost much of what they had gained through their imperial endeavors) is not necessarily accurate.
      The main reason reason behind deciding to use atomic weapons was that the quickly growing rift between the U.S.S.R. and the U.S. was expanding from day to day, and both were vying for power in the region. Stalin had just recently entered the war against japan (as it had always promised it would exactly 90 days after the European theater had been closed) and swept through Manchuria. The American leadership was starting to mistrust the U.S.S.R and realized that they needed to assure that japan would never be able to return to war against the U.S., and furthermore that it did not fall under soviet control.
      I should add as a footnote that I do not necessarily agree with the use of atomic weapons. I am just trying to understand why these things happen and what the people who made them so were thinking.
      (16 votes)
  • purple pi purple style avatar for user King Rufus Fufu HipHop Jungolingo Monkey Boy
    How come Hitler promoted people with blond hair and blue eyes when he didn't even have that?
    (14 votes)
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    • leaf green style avatar for user Aberwyvern
      The hair color was not important for promotion, in fact almost all field marshals of Nazi Germany had dark hair. I have often read that Hitler had a Jewish grandparent, but I have not found any evidence for this, so I think it is just a rumor started to make an ironic story.
      The rules that the Nazi regime used to distinguish between Jews and non-Jews were formalized in the Nuremberg laws, and it stated that a person with a single Jewish grandparent was not considered a Jew but a German so even if had a Jewish grandparent he would not be considered a Jew.
      (8 votes)
  • hopper cool style avatar for user Alphanumeric Khan
    Why did Lee Harvey Oswald assassinate JFK?
    (4 votes)
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  • leaf red style avatar for user Laura Cristina
    I Didn't understood What is the bay of pigs? and what is the cold war mainly about?
    (6 votes)
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  • piceratops tree style avatar for user madsenw
    where did hitler die do we know where he did
    (1 vote)
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  • hopper cool style avatar for user Yuuki
    what did going to the moon do for the U.S? (in other words why did we go to the moon?)
    (3 votes)
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    • blobby green style avatar for user adalbart989
      The main reason we went to the moon was the fact the Soviet Union was trying to get there and America wanted to get there first. Scientists also strongly supported the moon landing because the unprecedented amount discovery it made possible. Another factor was that JFK had promised to land a man on the moon and after he died that became a sacred creed that must be done. Lastly there was a lot of national pride involved in the space program, showing the might and power of America.
      (2 votes)
  • piceratops ultimate style avatar for user vjap
    What does totalitarian mean?
    (2 votes)
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    • blobby green style avatar for user William Pitch
      Totalitarianism comes from the root word "total". It means the government seeks to control all aspects of society, from hospitals to television. Any society that exerts that amount of control over their people is totalitarian, whether they identify as Communist, Fascist, Integralist, Falangist, Socialist, Capitalist, whatever.
      (9 votes)
  • aqualine ultimate style avatar for user Alex
    Where did the word D-Day come from?
    (7 votes)
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Video transcript

We finished off the last video entering into the Great Depression. It wasn't just a depression for the US. It was a depression for the world. But I want to back up a little bit, because I forgot to mention a very important fact that's hugely important to the rest of US history into the 20th century. And that's what happened in 1917, actually during World War I. And that's the Bolshevik Revolution. The Russian empire was overthrown by the Bolsheviks. And it became the Soviet Union, which you probably know was a communist state, and it became the United States archenemy over the rest of-- well, not over the rest of-- but near the, I guess, the second half of the 20th century. So with that out of the way, I just want to make sure you know that Russia is now the Soviet Union. Let's fast forward back through the Great Depression, and probably the one point when we're doing this very high-level overview that's of interest. And as you can see, even though the focus of this series of videos is on US interest, what's happening in the rest of the world is starting to become much more important, because the US is starting to become this really serious global actor. And so in 1933-- so this is right in the middle of this global depression, and Germany was especially hit hard because of all the damage done by World War I and the war reparations and all the rest. You have Hitler coming to power as chancellor of Germany. And it's interesting to note that it was actually-- he came to power in a democratic process. Chancellor of Germany is analogous to prime minister of other countries, and so essentially he was ruling a coalition. The Nazis, his party, did not have the majority. But they were able to control this coalition. Although it was a very weak one. But what they were good at is intimidating and rigging elections and all the rest. And so over the course of the rest of the '30s, essentially the Nazis consolidated power until we get to 1939. And the rest of the world would kind of watch Hitler. He was consolidating power. He came in democratically, but he was essentially consolidating power under himself, turning it into a dictatorship. He was militarizing Germany. People started to get concerned, but they all had the doctrine of appeasement. Hey, you know, let's just not make him too angry and maybe he won't start anything too bad. But in 1939, Germany invades Poland. And this is kind of viewed as the one event that kind of-- the straw that breaks the camel's back, so to speak. And so it begins World War II. So this is the beginning of World War II. And initially it's between-- I guess if you think about the great powers that initially get involved, it is the British Empire and the Soviet Union. France is involved. It quickly gets overrun by the Nazis. And what happens is that the US-- it wasn't like the situation with World War I where the US was trying to stay neutral. The US had recognized, especially FDR, Franklin Delano Roosevelt, he had recognized that Hitler was an aggressor, that he was, from FDR's point of view, definitely in the wrong here. So even from the beginning of World War II, the US did help support the Allies. So it would send arms and any other type of assistance. When Japan and Italy joined on the side of Germany, the US embargoed oil to Japan. The US was an exporter of oil to Japan. And you could imagine Japan did not produce a lot of its own oil, and oil is super important when you're trying to run a war machine. So that didn't make Japan too happy. So you fast forward to 1941, and you have Japan bombing Pearl Harbor. So until this point, US kind of played a non-direct role. It definitely supported the Allies. It did what it could economically and by providing military aid, but it did not actively participate in the fighting. But then December 7, 1941, the Japanese bombed the US Pacific fleet at Pearl Harbor. And that's a whole interesting debate because, or discussion, it was lucky for the US that a lot of the Pacific fleet was not there. But it was obviously this thing that convinced the US public that World War II was worth joining. So in 1941, because of Pearl Harbor, the US enters the war. And it enters the war in both arenas, both in Europe and in the Pacific. And then you fast forward. It goes against the Italians in North Africa. And then you fast forward to 1944, it actually enters into the fight in mainland Europe. This is the invasion of Normandy. This is D-Day. June 6, 1944. If you have ever seen "Saving Private Ryan," it starts with this. I've never stormed a beach, but I could imagine that's probably the most realistic reenactment of what it was like to storm the beach at Normandy. But you fast forward to 1945. And eventually, especially between the Soviet and the US, or I should say all the Allied forces, they're able to, I guess, win the European front of World War II. And then you fast forward to the end of that year. Japan was still kind of fighting pretty ferociously. And so the US-- and this is once again-- I could make many videos of this. We can debate the ethical implications of this. But the US develops the atomic bomb, ignites one over Hiroshima and then a few days later one over Nagasaki. And that essentially ends World War II. And so the outcome of World War II is you have two remaining superpowers. You have the Soviet Union, and you have the United States. And what happens after that is that you have the Cold War. These two huge powers, the Soviet Union is this communist country. It's obviously trying to create this communist sphere of influence. A lot of Eastern Europe was falling under Soviet sway. The United States, not a communist country, a very capitalist country, you can imagine. And this is something that gets confused a lot. The Soviet Union was communist, and it was totalitarian. Communism and Democracy aren't necessarily things that go against each other. But the Soviet Union had neither a capitalist system, nor democracy. It was both communist and totalitarian. And when I say communist, I'm talking about no private wealth. The state really owned all resources. The United States, on the other hand, was hugely capitalist. And you could imagine many people in the United States did not want any of this communism business to come to us. So you have this major battle that never really erupts into direct conflict between the Soviet Union and the United States. It's always done through proxies, through people who the United States or the Soviet Union is acting on the behalf-- or who are acting on behalf of the United States or Soviet Union. But you have the Cold War beginning. And it's called the Cold War because it wasn't a hot war. The United States and the Soviet Union never really fired bullets at each other. Instead, they supported other parties that would fire bullets at the Soviet Union. Or the Soviet Union would support other parties that would fire bullets at the United States. And for the United States, it was all about stopping communism. It was all about preventing this domino theory that if one country in a region would fall to communism, that other countries would. So the United States became a bit paranoid, or maybe it was justified. Either way, it was very concerned about the spread of communism. And the first time that this really gets tested-- and 1950 is an interesting year, because this is the first time-- obviously, the US had nuclear weapons as of 1945. But in 1950, the Soviet Union tested its first nuclear weapon. So now the Cold War is starting to get very serious. Both of these adversaries can now nuke each other if they wanted to. And also in 1950, you have Korea. And Korea, before World War II-- so that's a very small depiction of Korea-- it was a Japanese colony. But obviously, Japan had now lost. And so after World War II, it was split between an area, North Korea, which was influenced by the Russians, and South Korea, which was influenced by the United States. And it was split along the 38th parallel, and I know this is a super small diagram. We'll go into more detail when we do detailed videos about the Korean War. But in 1950, you have the North Koreans invaded the South. So it started the Korean War. The US sent troops. The North Koreans had China on their side, the Chinese army. The Soviets were also supplying them. But at the end of the day in 1953, you fast forward, it ends up being a little bit of a stalemate, because the end result was is that the original 38th parallel border gets, I guess, reinstated. But that was the first real conflict of the Cold War. And notice there were never US or Russian-- or I shouldn't say Russian-- US or Soviet troops directly firing at each other. The US were at war with the North Korean and the Chinese troops, but they were kind of proxies for the Soviet Union. And at the same time, as you can imagine, because you have these two adversaries, these two technically sophisticated adversaries-- they both had nuclear weapons-- it became very interesting on who can kind of dominate space. So you have this kind of space race developing in 1957. The Soviets are able to launch the first artificial satellite around the earth. This is Sputnik One over here. Some people think the first Sputnik is the one that had the dog in it. No, that came a few months later. That was Sputnik Two, actually. Had the picture of the dog here, but the dog eventually dies. But it was alive for a little bit in orbit. So that gets everyone freaked out. The US responds. Then in 1961 you have Yuri Gagarin. He's the first person in space, first human being in space. He returns safely. We eventually get up there-- or the United States eventually gets up there as well. And you fast forward all the way to 1969, the US is the first to be on the moon. So you have this space race. The two countries are really trying to one up each other. And at the same time that that's happening, you have-- and I bring this up just because so much happened during his presidency. In 1960, you have John F. Kennedy being elected kind of in the heart of the Cold War. And the other interesting thing is he was the first Catholic president, which people questioned. That by itself was interesting. But what was really interesting in his short presidency-- and I think you might know that only had really-- he actually became president in '61. This is an error. He was elected in '60, but he became president in '61. He had a very short presidency. He was assassinated in '63, but a lot happened in that short presidency. In 1957, right before he became president, you had-- oh, sorry. Not 1957. Let me get my years right. 1959 you had the Cuban Revolution. Cuba became communist. Fidel Castro takes over. It becomes communist. So you could imagine, the Americans didn't like a communist state so close to our own borders. So in 1961 we support some ex-Cubans, or some Cuban exiles, to try to invade Cuba. And that also can be a whole topic for another video. There's debates between the CIA and the Kennedy administration for who was to blame for it being such a failure, but it was a failure. So it was a huge embarrassment to the United States. And from the revolutionaries' point of view, the communist revolutionaries' point of view, they kind of viewed this as solidifying their hold of Cuba. It showed that they could fend off a counter-revolutionary assault. And then you have in 1962. We have these spy planes. And we see that the Soviets are starting to put these ballistic missiles in Cuba, which really freaks the United States out, because these ballistic missiles could reach any part of the United States. We actually had similar ones in parts of Europe and Turkey, but we don't like these things here. So we essentially used our Navy to, I would say, blockade any more arms shipments to the Soviet Union. So Kennedy really has this kind of stand-off with the Soviet Union during the Cuban Missile Crisis in 1962. And most people believe that this was the closest that the United States and the Soviet Union ever got to actually having a war, and which would have probably turned into a nuclear war. But the stand-off eventually got resolved. The Soviet Union agreed to remove their missiles. Well, one, not send anymore missiles and dismantle the ones that they had already set up. And this wasn't publicly stated at the time, but the United States also agreed to do the same thing for our missiles that were pointed at the Soviet Union, to remove those from Turkey. So the world, at least at that point in time, had avoided a mutually assured destruction. The whole time that this is happening, remember, the United States is paranoid. And maybe justifiably so. Paranoia usually means worried when there's not a cause. But maybe justifiably worried about the spread of communism. You have a situation where, in Vietnam, you have a Vietnam, which is right about-- let me make sure I circle the right country-- you have in Vietnam the communists come to power in North Vietnam. This was formally a French colony. The US, right from the get-go in 1950, start sending advisers to aid the anti-communists in South Vietnam. In Kennedy's administration, the amount of advisors-- and I should probably put that in quotes, because these advisers started becoming much more involved-- really grew. And until 1965, the United States started sending it acts actual official combat troops to fight in Vietnam. And you fast forward that all the way to 1975. And the reason why this is significant, other than this being one of the more recent major wars the United States has been in, it's the first war that the United States kind of unambiguously lost. In 1975, the last presence of the United States left. And essentially Saigon, which was the capital of South Vietnam, fell to the communists. So I'll leave you there, and we're now essentially in modern history. At least from my point of view, because I was born not too long after that. Anyway, hopefully you found that interesting. Let me, oh, I couldn't find the stop button. There you go.