"But what if it was not and the aircraft was deliberately targeted in an attempt to further isolate the Ukraine from the West."
That doesn't make sense, actually it has pushed Ukraine closer to the West than it has ever been.
Also it provided "breathing room" for ukrainian aircraft and they are now pounding rebel cities fiercely without fear from their SAMs (as rebels can't risk anymore with SAMs) and without any care for civilian casualties as media is now interested solely in MH17(we can also add Gaza to that).