The two Terran Cold Wars were the predominant global conflicts of the middle 20th and early 21st centuries.
First Cold War
The Communist and Capitalist blocs, heralded by the Union of Socialist Soviet Republics (USSR) and United States of America (USA), entered into a prolonged ideological, political, and economical competition. Unlike previous wars, where the threat of mutual nuclear annihilation did not yet exist, the Cold War was mainly fought through proxy and economic wars. Both ideological blocks coalesced into treaty organizations, the Warsaw Pact Nations on the one hand and the North Atlantic Treaty Organization (a predecessor of the Western Alliance) on the other.
Eventually, the arms race escalated into a space race. While the USSR was the first to put a man into space, the USA put the first man on Luna, the Terran moon. Soon, space-based weapons like the Excalibur satellites were developed by the USA to counter the USSR's ever increasing nuclear arsenal and newly-developed accurate missile delivery systems.
Thanks to the ever increasing armament costs and the militarization of space, the economy of the Soviet Union finally collapsed in 1988, and a reform government under Mikhael Gorbachev took power on the 11th of January. The Soviet Union was officially disbanded and Russian troops began leaving the Warsaw Pact nations.
With the sudden end of the First Cold War, the victorious powers drastically cut their military funding, which promptly lead to a global recession. Experienced western politicians cut taxes, encouraged trade, and finished building the last big weapon and defense systems (like Crippen Station). The successor of the Soviet Union, the Russian Federation, was not so lucky. While attempting to reform the Russian Federation into a Capitalist nation, Russia's leadership merely aped the most libertarian politics of the NATO states. Coupled with an increased need to maintain internal and external power projection and keep uprisings in the Afghan SSR down, Russia was plunged into a deep depression.
Second Cold War
After the Soviet Union was reestablished by a hardliner coup in 1997, tensions between the newly-renamed Republic of Russia and the NATO member states steadily escalated after the reoccupation of the Warsaw Pact nations. Initially, neither side was militarily strong enough to escalate the conflict beyond posturing. However, Russian economic weakness was masked with military saber-rattling and by 2004, World War III seemed to be imminent.
In the end, even the most hardline Soviet politicians realized that the Soviet Union was economically bankrupt, militarily weak, and politically finished. The Second Cold War ended after the election of a new Soviet Premier; despite the beginning de-escalation during the last few months of the conflict, NATO opted to launch the newly finished Crippen Station into orbit, where it formed the heart of the Western Orbital Defense Network.
Compromise candidate Oleg Tikonov ascended to the Premiership in 2004, and cautiously began undertaking demilitarization, liberalization, and rapprochement with NATO. Hours after signing the Tikonov Accords, Tikonov was assassinated and the Second Soviet Civil War began. 
- Cold War
- Jihad Hot Spots: Terra, pp. 138-139