The routing has been commented on, but only a little. Who sets the route? Air traffic control? Does the pilot have a choice?
I'm not a pilot, but pure logic tells me that when flying in another country the pilot may only suggest the route, subject to approval of the ground controller. For example, are Chinese pilots free to fly over any area of the USA?
A pilot always has the right—for safety reasons—to make the decision to accept a routing. If the controller is not able to give the pilot a routing he likes, the pilot may declare an emergency, which in most cases will force the routing he wants onto the air traffic control system. Outside of an emergency, a civilian pilot may not stray into restricted airspace without approval of air traffic control.
If the routing in a pilot-declared emergency takes the pilot into restricted areas or where other traffic may be a problem, the controller will apprise the pilot of that if at all possible, and reroute the other traffic as needed and if possible.
I believe part of the controversy is that some deem ICAO (International Civil Aviation Organization) should have declared the eastern Ukraine restricted airspace, through which no controller would then give a civilian craft clearance, except related to an emergency.
If a pilot crosses into forbidden airspace, fighters from the transgressed country may be scrambled to accompany the flight and make whatever demands of the pilot their military/government deems appropriate.
In more peaceful scenarios, diplomats will be left to work through the details of transgressed airspace. In more belligerent cases, guns and missiles may determine the outcome.
If the rebels shot down MH17 (without further complication), whoever they organizationally are should be shouldering the burden of compensation to the victims. If they’re paper-thin proxies for Russia, those “chickens may come home to roost.” To the extent the possible proxy question comes clear through this situation, I think the world will welcome that aspect.
HF