In 1945 the USA used nuclear weapons to bomb the Japanese cities of Hiroshima and Nagasaki. The casualties number over a hundred thousand. The world stands in awe and fear of America's new superweapon.
Combating the world's new superpower becomes the sole aim of Soviet military scientists, and funding is poured into several projects, few of which produce anything beyond ineffectual prototypes. One of these projects, Project Elbrus (Russian: Проект Эльбрус - Proekt Elʹbrus, named for the highest mountain in the Caucasus mountain range), produces a working electrolaser. This uses the blooming effect of a laser to produce a line of ionized plasma, along which a powerful electrical current can then be sent, in a manner similar to lightning. The prototype is inefficient, weak and unwieldy. Soviet military commanders see no real practical use of the technology, and funding is cut in order to further develop the Soviet Union's own nuclear weapon, rather than develop counter measures to it.
On the 12th of December, 1950 General Secretary Joseph Stalin sends America an early Christmas present: the USSR conducts its first nuclear weapons test at the Semipalatinsk Test Site in the Kazakh SSR.
By 1961 the USA's nuclear stockpiles have grown immensely, whilst the Soviets still languish behind. Convinced that a nuclear war with America is imminent, First Secretary Nikita Krushchev begins looking for a method of effective defence against a nuclear strike. Isaac Bahdanovich, the Byelorussian scientist that headed Project Elbrus, suggests that a sufficiently advanced electrolaser could disable a nuclear weapon in flight. Project Motherland (Russian: Проект Pодина - Proekt Rodina) is set up to explore the plausibility of developing and deploying advanced electrolasers in this manner. Krushchev is deposed in 1964, but the project continues.
In August, 1966 a computer-controlled electrolaser with a radar targeting system is shown to be able to intercept nuclear missiles in flight. The system is still too expensive and inefficient to be deployed on any national scale, so development continues.
By 1970 Project Motherland has produced a suitably efficient production model of a radar-targeted electrolaser. This technological advance is hidden from the public until 1973, when the last of the first generation of anti-nuclear electrolasers is constructed. Senator Lee Metcalf comments that President Nixon's teeth-grinding could be heard all the way from Capitol Hill.
In order to test western zeal in face of their new defence system, Soviet troops "accidentally" cross the border with Finland whilst "on maneuvers" and, supposedly believing they are still on Soviet soil, open fire on Finnish troops that attempt to approach them. Many western politicians do not make mention of the issue, whilst others, such as President Nixon, begrudgingly claim that they hope that the situation can be solved peacefully and without further bloodshed. Believing this to be a weak response on the USA's part, the USSR makes claims that the Finnish troops opened fire on the Soviet troops first. Finland refuses to allow Soviet military observers into the country to investigate the issue. After a short and brutal war, Finland is absorbed into the USSR as the Finnish SSR in early 1974. The western world deplores this blatant warmongering, but resolves to do nothing about it.
Now believing the USSR free of the threat of nuclear war, General Secretary Leonid Brezhnev pursues a policy of promoting world communism, and espouses the idea of a "Worldwide socialist union". These policies develop as time moves on, and the USSR begins integrating its allies into the Union.
By 1985 Poland, Czechoslovakia, Bulgaria and East Germany have been integrated into the USSR. General Secretary Andrei Gromyko and Mongolian President Jambyn Batmönkh announce plans to integrate Mongolia into the USSR, drawing the anger of the People's Republic of China. The depth of the Sino-Soviet split shows when, on the 30th of March, 1985, the Politburo of the Communist Party of China under Hua Guofeng - Mao Zedong's designated successor - declares war on the USSR. The hope is that the other nations of the world will declare war on the Soviet Union, and that their combined might could overcome that of the USSR. The hope is forlorn on both counts.
After the swift and brutal crushing of Chinese military forces, China is reorganized with a pro-Soviet government in charge. Manchuria is annexed directly into the Soviet Union as the Manchu People's Soviet Socialist Republic.
Following pressure from Moscow, and increased US military presence in South Korea and Japan, the Democratic People's Republic of Korea is incorporated into the USSR in 1988.
In 1989 the Berlin Wall comes down, and West Berlin is incorporated into the German Soviet Democratic Socialist Republic after the USSR demanded the transfer of the territory, officially to end the suffering of the isolated people of West Berlin and to end the exclave as a relic of a bygone era, unofficially as part of a move to consolidate their existing territories before expanding further.
It is now 1991. God help us all.
(Note: I'm aware that electrolasers may not actually be of any use in shooting down nuclear missiles and that the Soviet Union developing practical electrolasers in this manner is highly implausible. This map was made for a contest where a major power develops an ultimate weapon - of sorts - and this was my entry.)
(Edit: For full size right click on the image and click "View image" or "Copy image URL" and paste the URL into your address bar, or get V7 fixed somehow.
(Editedit: Okay, dA keeps squishing the map down so it looks compressed and ugly, if you want to see the map in all its original glory, please click here: [link]
(Edit: Corrected map to show the correct location of Alma-Ata/Almaty, the Kazakh SSR's capital city, as I somehow managed to get the location mixed up with the modern capital of Astana.)