<Table> <Tr> <Td> </Td> <Td> This article contains Korean text . Without proper rendering support, you may see question marks, boxes, or other symbols instead of Hangul and Hanja . </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This article contains Korean text . Without proper rendering support, you may see question marks, boxes, or other symbols instead of Hangul and Hanja . </Td> </Tr> <P> In the U.S., the war was initially described by President Harry S. Truman as a "police action" as it was an undeclared military action, conducted under the auspices of the United Nations . It has been referred to in the English - speaking world as "The Forgotten War" or "The Unknown War" because of the lack of public attention it received both during and after the war, and in relation to the global scale of World War II, which preceded it, and the subsequent angst of the Vietnam War, which succeeded it . </P> <P> In South Korea, the war is usually referred to as "625" or the "6--2--5 Upheaval" (6.25 동란 (動亂), yook - i-o dongnan), reflecting the date of its commencement on 25 June . </P>

What happened first korean war or vietnam war
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