Militarization of the SCO in 2012-2013
The cowardly attack on Pakistani soldiers will decisively strengthen the anti-US faction in Pakistan against the pro-US faction. A major deterioration of the relationship between Pakistan and the US due to the attack will likely lead China and Russia to agree to militarize the SCO in the next 1 or 2 years. China and Russia have been unable to agree on militarization for the past few years, but now many factor push toward militarization of the SCO:
1) In March 2012, China will be undergoing a leadership change. A pro-military, hardline leadership is coming to power in Beijing.
2) Russia has a serious conflict with the US over missile defense in Eastern Europe and Syria. Russia's biggest dream is to trap and wound the US in Afghanistan the same way the US trapped and wounded USSR in Afghanistan in 1980's.
3) The US is acting more and more aggressively around the world, like taking military action against Libya.
4) Popular unrest in the Middle East is destabilizing the whole region.
The most likely formula is to only let Pakistan into SCO, but not india (as Russia prefers but not China), because india wants to "remain neutral" but secretly favor USA against Russia / China.
Once the alliance members are decided, then the SCO can strangle supplies to Afghanistan and hand the US a devastating defeat. The US will try to attack Pakistan by air and sea to save its troops in Afghanistan but China and Russia can send military equipment and advisors to counter them. Within a few months, all the coalition troops Afghanistan should have surrendered to the Taliban.
So it's very likely we'll see a final military showdown between SCO (composing of China, Russian, Central Asian -stans and Pakistan) versus US military with Afghanistan, Arabian Sea, Indian Ocean and possibly even Syria or Iran as theaters of war.