The Soviet Union and some communist states have been accused on numerous occasions of sponsoring international terrorism especially during the Cold War. NATO and also the Italian, German and British governments saw violence in the form of "communist fighting organizations" as a serious threat.
According to Soviet defector Grigori Besedovsky, the NKVD was directly coordinating a number of bombings in Poland as early as in the 1920s. The largest bombing, against Warsaw Citadel on 13 October 1923, destroyed a large military ammunition storage facility, killing 28 and wounding 89 Polish soldiers. Another bombing on 23 May 1923 at Warsaw University killed a number of people, including professor Roman Orzęcki. Further bombings happened in Częstochowa, Kraków and Białystok.
Soviet secret services have been described by GRU defectors Viktor Suvorov and Stanislav Lunev as "the primary instructors of terrorists worldwide." The terrorism was seen by Soviet leadership as the only way to reduce the imbalance between USSR military and economical power against the Western world. According to Ion Mihai Pacepa, KGB General Aleksandr Sakharovsky once said: "In today’s world, when nuclear arms have made military force obsolete, terrorism should become our main weapon." He also claimed that "airplane hijacking is my own invention" and that in 1969 alone, 82 planes were hijacked worldwide by the KGB-financed PLO.
After defeat of Soviet-controlled Arab states in the 1967 Six-Day war, Soviet Union started a widespread undercover campaign against Israel, involving propaganda as well as direct military support (funding, arms, training) to terrorist groups declaring Israel as their enemy. Additionally, the USSR took the decision to increase anti-Israeli sentiment by disseminating anti-Zionist propaganda and even referencing previous anti-Semitic tropes from Western culture, such as the Jewish-Freemason conspiracy theories. The overall goal of the campaign was to spread the idea that the state of Israel was an oppressive, imperialist state which was built on unjust terms, a feeling expressed in the Soviet-crafted UN General Assembly Resolution 3379. Meanwhile, the cause of the Palestinian people who had suffered mass displacement and deportation with the establishment of the state of Israel and the subsequent wars in the region was promoted and the USSR gave active support to certain Palestinian rebel groups whose primary method of struggle is characterised as terrorism, such as the Palestinian Liberation Organization (PLO).
Lt. General Pacepa described operation "SIG" (“Zionist Governments”) that was devised in 1972 to turn the Arab world against Israel and the United States. According to Pacepa, the following organizations received assistance from the KGB and other Eastern Bloc intelligence services: PLO, National Liberation Army of Bolivia (created in 1964 with help from Ernesto Che Guevara), the National Liberation Army of Colombia (created in 1965 with help from Cuba), Democratic Front for the Liberation of Palestine in 1969, and the Secret Army for Liberation of Armenia in 1975.
The leader of the PLO, Yasser Arafat, established close collaboration with the Romanian Securitate service and the Soviet KGB in the beginning of the 1970s. The secret training of PLO guerrillas was provided by the KGB. However, the main KGB activities and arms shipments were channeled through Wadie Haddad of the DFLP organization, who usually stayed in a KGB dacha (BARVIKHA-1) during his visits to the Soviet Union. Led by Carlos the Jackal, a group of PFLP fighters accomplished a spectacular raid on the Organization of Petroleum Exporting Countries office in Vienna in 1975. Advance notice of this operation "was almost certainly" given to the KGB. Faisal al-Shammeri credits Soviet special services with sponsoring international terrorist organizations that emerged in Libya in 70-80's, Palestine Liberation Organization, Popular Front for the Liberation of Palestine, as well as continuation of these policies after the fall of the USSR.
The Red Army Faction in Germany was over years the supported by the Stasi, East Germany's security service. In 1978 part of the RAF group (Brigitte Mohnhaupt, Peter Boock, Rolf Wagner, Sieglinde Hoffmann) was hiding in a Służba Bezpieczeństwa (SB) safe house in the Mazury district in Poland, where they escaped through Yugoslavia. During the stay, they were training together with Arab operatives and also hiding from German police during an intensive search for the group's members in West Germany. Carlos the Jackal and other prominent terrorists, such as Abu Nidal, Abu Daoud and Abu Abbas, enjoyed protection at SB safe houses in Poland, especially in the 1980s. Communist Poland was also used as a transit country for money and weapon transfers for these organisations.
A number of notable operations have been conducted by the KGB to support international terrorists with weapons on the orders from the Soviet Communist Party, including:
Large-scale sabotage operations may have been prepared by the KGB and GRU in case of war against the United States, Canada, United Kingdom and the rest of Europe, as alleged by intelligence historian Christopher Andrew in Mitrokhin Archive and in books by former GRU and SVR officers Victor Suvorov and Stanislav Lunev, and Kouzminov. Among the planned operations were the following:
According to Lunev, a probable scenario in the event of war would be poisoning of the Potomac River with chemical or biological weapons, "targeting the residents of Washington, D.C." He also noted that it is "likely" that GRU operatives have placed already "poison supplies near the tributaries to major US reservoirs." This information was confirmed by Alexander Kouzminov, who was responsible for transporting dangerous pathogens from around the world for the Soviet program of biological weapons in the 1980s and the beginning of the 1990s. He described a variety of biological terrorist acts that would be carried out on the order of the Russian President in the event of hostilities, including poisoning public drinking-water supplies and food processing plants. At the end of the 1980s, the Soviet Union "was the only country in the world that could start and win a global biological war, something we had already established that the West was not ready for," according to Kouzminov.
At its height, communism was the major threat to world peace, and by far the major source of international terrorism: that is, communist-inspired and/or communist-supported terrorism. Its hold on terrorist movements was not universal, however [...].