MIGHT not be responsible for the downing of Malaysian Airlines Flight MH70, but, assuming he armed those who committed this unspeakable, monstrous atrocity, he is sure as hell ACCOUNTABLE.
He gave them the weapons, the sophisticated weapons they otherwise would not need EXCEPT to shoot at high altitude aircraft. They did not need SA-11, phased-array guided Surface to Air Missiles to defend themselves from aerial attack by the Ukranian "Air Force." These were offensive weapons which had to be deployed in a large area following sophisticated training. Training his generals provided assuming these weren't in fact OPERATED by Russian regular military personnel. He armed them in the manner of a regular, modern army and he set them loose. These aren't weapons which any average soldier, let alone person, could have figured out how to fire. It required extensive, specific training to prosecute and shoot down an airliner flying at 35,000 feet. It requires connecting control radar, fire control computers and the firing platforms to each other, understanding those protocols AND knowing which buttons to press in which order to bring the radar online, to target the "right" aircraft, and finally to target, arm and fire the weapon.
These people, people who were trained almost certainly by active military personnel, appear (very strongly) to have killed almost 300 people, perhaps by mistake, but whether it was a mistake is NOT material. Assuming it's the Pro-Russian "separatists" (read Russian operatives) then he, PUTIN, is accountable for what they've done. Just like the bartender who gives the irresponsible drunk another drink and hands him the keys to the drunk's car, HE is accountable for their conduct once he gave them these weapons.
Damn Putin, damn his reckless, power-mad bear wrestling hide. He could have set the world on course to war with his irresponsibility. The vultures are circling and the hawks are calling. I hope the President decides to meet out justice for the guilty. I hope we isolate Russia on the world stage and that our European partners are willing to pay the price to do so, and do that which they've heretofore been unwilling to risk and to pay, and so President Obama had to go it alone. I hope we can avoid war and I believe Mr. Putin, assuming what appears almost certainly to be true, IS true, well, I believe Vladimr will burn in the hell of his own making forever. He'll certainly deserve it.