9. JB, speculating: Re the idiotic, "East-West struggle" in Ukraine, don't rule out the possibly drunken "hired hands" in this bloody affair handling sophisticated military equipment they know nothing about, except pushing its buttons to blow people up. Reminds me, granted in a quite different context, of the performance of USA military contractors in Iraq. If this tragic stupidity had happened during the Cold War, you'd not be reading this blog entry. Feeling nostalgic, if you are of a certain age? Or would you prefer to be dead already?
See also.

Update (July 19): 

Prime Minster [sic] Arseniy Yatsenyuk, in an interview with CNN on Saturday, also suggested that whoever operated the missile system had had expert training.

"This is not the Russian-led drunk terrorist who pressed the button," he said. "This is someone well trained. Someone who knows how this machine works. Someone who has experience."

One more update (late afternoon, 7/19): My favorite Russian saying:

"Pozhar idet po planu -- The fire is going according to plan."

Another Update (July 21):

"A half-drunk Ukrainian peasant with a 1950s-era rifle doesn’t shoot down a
plane at 33,000 feet." - Roger Cohen, New York Times (and yet, in the next paragraph of his piece cited here, he writes:  "In June, a Ukrainian cargo plane landing in the area was hit with shoulder-fired missiles, killing 49 people. This month, another cargo plane flying at 22,000 feet was hit by a missile. Rocket science is not required.")

Another update (July 22):

To put it simply, these “rebel” armies, are one of the largest Russian military intelligence operations in a generation. But, it would seem, despite being armed with sophisticated rocket launchers, they were unable to tell the difference between a Malaysian Airlines passenger jet and a Ukrainian military transport plane. This is because, out in the field, the Russian army’s special operation forces (who are supporting the separatist rebels) have been unable to combat the corruption, incompetence and incoherence which brought about the military bungles in Beslan a decade ago when Russian military stormed the besieged school causing horrific chaos and the loss of 334 lives.

Yet another Update (July 22):
“Drunken — I mean literally, drunken — separatist soldiers are piling bodies into trucks unceremoniously and disturbing the evidence,” Secretary of State John Kerry said on “Fox News Sunday.”

Read more: http://www.politico.com/story/2014/07/a-hell-of-a-world-109194.html#ixzz38EkZ1Ew3

What caused Malaysia Airlines flight MH17 to crash into a field in eastern Ukraine killing all 295 on board? The truth will only be known when someone admits to causing the plane to crash, when satellite data reveals whether it was shot down or crashed, or when the full investigation, some months off, gives its final report.
However, trying to make sense of the disaster, reporters are putting to experts on aviation and ground-to-air weapons a number of alternative scenarios. Here are the options that are being explored:
1. Kiev forces shot down the plane on purpose. Highly unlikely and the Ukrainian president, Petro Poroshenko has firmly placed the blame on the separatist rebels who hold the part of eastern Ukraine where the plane was downed.
The war is slowly turning in favor of the Kiev government forces, so it would be rash to invite international condemnation for such a blatant act of unnecessary aggression against a civilian airliner of a third-party country.
2. Kiev forces shot down the plane by accident. Possible but still unlikely as the Kiev forces are well trained and disciplined and are under clear instructions to do nothing that might provoke the wrath of the U.S. and E.U.
3. Pro-Russian separatists shot down the plane on purpose. Possible as they have shot down a number of Kiev forces military aircraft before, though those planes and helicopters were flying far lower than flight MH17.
However, the separatist rebels may have been trying out a weapon, though they deny their Russian provided weapons are capable of reaching airline routes. But as the rebels are the least disciplined of the forces under scrutiny, this may ultimately prove to be the true explanation.
Confident that the crash was “a terrorist act” by Ukrainian separatists, Poroshenko has invited Dutch investigators to determine exactly what happened. Separatist forces on the scene have taken control of the black box recorder that will hold the key to what happened.
Shortly after the plane hit the ground, Igor Girkin, a separatist took to the VKontakte social network with: “We just downed an An-26 near Torez. It's down somewhere near Progress mine.” That may have been merely an empty boast. Not long after, the post was removed.
4. Pro-Russian separatists shot down the plane by accident. Possible. Though as they hotly deny responsibility for the crash and insist they do not have the weapons to pull off such a trick, only a full investigation will reveal who fired the missile, if indeed MH17 was shot down.
5) Russian military missiles shot down the plane on purpose. Highly unlikely. Having suffered renewed and painful U.S. and E.U. sanctions this week, Russian President Vladimir Putin does not want to escalate tensions in the Ukraine further. On the contrary, everything he has been doing and saying lately has suggested he wishes to play down Russian involvement in the Ukraine conflict. Putin will know from his military’s satellite pictures whether the plane was shot down or crashed. 
6. Russian military missiles shot down the plane by accident. Again, highly unlikely. No one in the Russian military dare make a move unless it has been given the OK from the Kremlin. Putin has ruled out direct military involvement not least because he has been getting his own way in Ukraine by stealth.
7. It was an accident caused by mechanical or pilot failure. Always possible, but unlikely. The Boeing 777 like the one that crashed is one of the safest airliners flying today.
8. MH17 was brought down by an act of terrorism, either by a terrorist on board or by the planting of a bomb. Unlikely. Usually acts of terrorism are claimed by the terrorist organization responsible without delay, and no one has yet claimed responsibility.