text: what started the vietnam war, and how does it compare to the war in iraq? people often talk about iraq having similarities to vietnam. why did the vietnam war happen? some of the other answers have good points, but .... what actually started the vietnam war will always be debateable.  i've studied vietnam and the vietnam war for many years, and i continue to find more questions than answers about the war. one thing i can tell you for sure is the war was inevitable, however u.s. involvement was not.   you can trace reasons why the war started back into the mid-1800's when the french colonized vietnam, cambodia and laos in creating what was then indochina. vietnam has a very long history (literally 1,000's of years) fighting against those who had tried to occupy or control their country. sooner or later, the vietnamese people would rise up to kick the french out of their country as they have with the chinese, japanese and mongols in the past.   when the french failed to keep their promise of independence to vietnam after wwii, all hell broke loose to say the least. for lack of better words, the u.s. and it's coalition (yes, there were other countries that fought with the u.s. in  vietnam) became involved to clean up france's mess. this snowballed into a much bigger conflict than the one that france was involved in.   it could be seen that the iraq and vietnam wars are similar on the surface, but they're actually worlds apart in just about every aspect. to consider these war similar in any way other than coincidential would be due to ignorance and lack of knowledge of either conflict and the countries involved.