In 1968, Kahane was one of the co-founders of the Jewish Defense League (JDL) in the United States. In 1971, he co-founded Kach ("Thus"), a new political party in Israel. That same year, he was convicted in New York for conspiracy to manufacture explosives and received a suspended sentence of five years. In Israel, he was convicted for plotting to blow up the Libyan embassy in Brussels in revenge for the massacre of 11 Israeli athletes at the 1972 Summer Olympics in Munich, receiving a suspended sentence and probation. In 1984, he became a member of the Knesset, when Kach gained its only-ever seat in parliamentary elections. Kahane was boycotted across the aisles of the Knesset, and would often speak in front of an empty chamber. The Israel Broadcasting Authority similarly avoided coverage of his activities. The Central Elections Committee tried to ban Kahane from running in the 1984 elections, but this ban was overturned by the Supreme Court because there was no law to support it. In response, the Knesset approved an ad hoc law that allowed for the banning of parties that are "racist" or "undemocratic". In 1988, despite polls showing Kach gaining popularity due in part to the ongoing First Intifada, Kach was banned from entering that year's elections.