Bit of a rush job, but I thought I might as well have a bash.

The two decades between Chinese Crisis of 1989-90 and the Sino-Soviet War in 2014 were a golden age for the USSR. Relations had already been improving between West and Soviets, and during the Chinese crisis they found themselves allied with Britain as they both fought the People's Republic of China. After the war relations only improved. Regulated free enterprises helped boost the economy, as the the rise of India. Corruption was being cracked down on there was increasing political freedom. Things were looking great, but everything changed with the Chinese attacked.

The PRC had been seething for those same 20 years. The nation was still controlled by Maoist hardliners, who wanted revenge for what had happened in 1990. In late 2014 there was a cross border incident with the Mongolian People's Republic. China used this as a pretext for an invasion, and refused to leave, claiming Mongolia was rightfully part of China. The USSR moved in to support their loyal ally and their superior weaponry and leadership allowed them to easily take back Mongolia. Soviet troops pushed hard, forcing their way into inner Mongolia and capturing the cities of Baotou and Hohhot.

The PRC's government panicked, their army seemed unable to stop the Soviet advance and they decided to use a tactical nuclear weapon to stop them. They got away with it, killing thousands of Soviet soldiers and Chinese civilians. The USSR followed this with a declaration of war and prepared for a full invasion. The Chinese decided a limited strategic attack was necessary and launched several nuclear weapons at Siberian and Mongolian cities that would likely have been used as staging posts, the USSR responded with a full strategic strike and the Chinese reciprocated.

The devastation was massive, the PRC was utterly destroyed. Currently China is a radiative wasteland, with only a few lucky areas being occupied by the ROC or warlords. The USSR has faired little better. The Soviet and NATO missile shields spared some of the west, but most of the nation is lucky to have anyone left alive in it, let along a government.

The Soviet Union still clings on, currently based in Petrozavodsk, with strongholds in Bulgaria, Crimea, Central Asia and the Russian Far East, which came though the war with little direct damage because the Chinese did not want to risk irradiating themselves by nuking somewhere so close to them, and once the war turned really nasty Japanese missile defence was able to protect them.

After the war the USSR had little choice but to let the Baltic states have their independence and gave up without a fight. There were a few half-hearted attempts to hold onto the Caucuses, but the USSR quickly abandoned the region after the managed to work out a deal with the Azaris to provide them with oil, which has lead to a great deal of local squabbling.

While the Bulgarians survived unscathed and have long been extremely loyal to the USSR, there is a growing resentment on how much the rest of the Union is relying on them. Many feel they are shackled to a corpse and need to leave before their economy collapses under the pressure.

Belarus and Ukraine have already left, their nationalistic governments paying lip service to the west to ensure their independence.

In eastern Russia a nationalist government has been set up in Pskov, the USSR plans on dealing with them as soon as they make sure they don't have any nuclear weapons stashed away.

During the chaos Romania saw it's chance and invaded Moldova up to the Dniester. While there is plenty of propaganda footage of smiling Moldovans welcoming Romanian troops, reports of ethic cleansing of the Russian and Ukrainian population are increasing. Dictator Ion Fărcăşanu denies any involvement.