>>but I do honestly think they were thinking that plane was a ukrainian militairy plane and deliberately shot it out of the sky

I guess it can be difficult to tell the difference when the plane's 33,000 feet up. FWIW if you look at the flight path, it seems unlikely you could believe it was an internal Ukranian flight. Maybe some civilian airlines believed that flying so high pretty well excludes the possibility of an internal flight so it's safe... though international and US authorities had suggested not flying over the Ukraine, not least because somebody has been shooting down aircraft for some weeks now. Meanwhile some people are saying that the aircraft was further North than usual, taking it over a fiercely contested area. Conspiracy theorists are having a field day.