Some quick thoughts on the shootdown of Malaysian Airlines flight 17:
There are three likely possibilities as to who shot the aircraft down: Ukrainian military forces, Russian-aligned separatists (with or without Russian military assistance), and finally one of these two forces attempting to make it look like the other committed the act.
It looks as if the US may have tracked some part of the missile launch, possibly using the Space Based Infrared Radar system of satellites. It is highly likely that US national technical assets will be able to approximate the point of origin of the launch, and the launcher. This means it will be up to the US to make the case as to who fired the missile, potentially putting Washington in a position of greater direct confrontation with Russia (beyond recently announced sanctions).
The priority for the UN Security Council is to secure international access to the crash site rapidly, before evidence can be destroyed or disturbed. Australia is ideally positioned to lead an international crash investigation team. For a start, we are not the US or Ukraine. Secondly, we have highly skilled air crash investigators, who have recent experience working with Malaysian Airlines on the MH370 crash. The Australian Government should consider volunteering Air Chief Marshall Angus Houston to lead the air crash investigation, given the international trust he has built on the MH370 search and his previous military experience.
Australia should consider the possibility that technical and possibly security support will be needed for the crash investigation and should be prepared to offer both. Given the proximity to the Russian border, NATO and the OSCE will not be ideally positioned to contribute to this effort. Armed police, as opposed to military, may be a less provocative solution to guarantee security for air crash investigators.
If Russian-aligned separatists are shown to have fired the missile, it may provide the catalyst necessary to enlist Russian cooperation to de-escalate the Ukraine crisis.
If on the other hand this is the result of a mistake by the Ukrainian military, this will embolden Russia and aligned separatists and lengthen the conflict.
Just hours after Brigadier General Gilbert Toropo delivered a cautiously upbeat address to the parade marking the end of his first year as Commander of the Papua New Guinea Defence Force (PNGDF), a handful of his troops threatened to undo any progress he had made.