This is right. It has been pointed out that both the Ukrainian government and the rebels now have the capability to do this, the Ukrainian government has had it for a long time, without incident. Because under a government it is operated by soldiers who follow procedures and have access to the data about known civilian flights.
It gets a bit worse than that I believe, officially to this date the blame is still on Iran for flying an airliner according to it's flight plan and in the commercial traffic corridor.
They shot down a A300 thinking it was an F14, and they were in a heightened level of alert because they (the USS Vincennes) were in Iranian waters, chasing a small naval boat that they claimed shot at their helicopter.
As an aside, the IR655 tragedy was one of the first were data was available to separate fact from fiction.