The JDL are widely viewed as extremists by the great majority of American Jews. No mainstream Jewish organization has any ties to the JDL. Many rabbis from all the Jewish denominations have condemned the JDL as extremist. Recent newspaper reports indicate that membership in the JDL appears to be limited to a few dozen people.
JDL members have been accused by the FBI and CIA of 37-50 terrorist attacks, including: bombing of the San Francisco branch of Melli?, an Iranian bank, in 1981; bombing the Iraqi UN mission in 1982; bombing the offices of [Sol Hurok]?, who organized performances of Soviet ballet? in the United States (resulting in one death); bombing the Los Angeles offices of the [Arab Anti-Discrimination Committee]? in 1985 (killing its director, [Alex Odeh]?); and bombing and killing [Tsherim Soobzokov]? (a Wafen-SS veteran) in 1985. In these cases an anonymous caller would claim JDL responsibility for the bombing, which was then denied by the JDL leadership, although often they would say that, although they had nothing to do with it themselves, they were happy the attacks had occured: for example JDL chairman [Irv Rubin]? said Odeh "got what he deserved", although they insist the attack was done by Arabs, not by them. (Sources: [1], [2])
The motivation for JDL attacks against the PLO, Iraqis, Iranians and a Waffen-SS veteran are obvious; the primary motivation for attacks on Soviet targets such as Sol Hurok was the refusal of the Soviet government to permit Jewish emigration from the Soviet Union to Israel.
After 1987, when several JDL members were convicted on terrorism charges, JDL terrorist activity appeared to have ceased. More recently however, its chairman, [Irv Rubin]?, 56, and another member were arrested by members of a federal anti-terrorism task force (reported on December 12, 2001) on suspicion of plotting to bomb a Los Angeles mosque and the office of US Congressman [Darrell Issa]?, a Christian of Arab-American descent.
JDL has also defended the massacre of 29 Arabs in Hebron by Dr. [Baruch Goldstein]?, a former JDL activist, in February 1994, saying "we feel that Goldstein took a preventative measure against yet another Arab attack on Jews. We understand his motivation, his grief and his actions. And we are not ashamed to say that Goldstein was a charter member of the Jewish Defense League." ([2]).
On December 12, 2001, [Irv Rubin]?, the Chairman of JDL, and Earl Krugel, a member of the organization, were officially charged with conspiracy to commit an act of terrorism. The two were caught in the act of planning a bombing of Arab-American Congressman [Darrell Issa]?'s office and the King Fahd Mosque in Los Angeles. The two were arrested as part of a sting operation when they received a shipment of explosives as Kugel's home in L.A.
External Links:
http://www.jdl.org/ -- Jewish Defense League website
http://www.securitymanagement.com/library/000248.html -- Information on JDL terrorist activities
http://www.salon.com/news/wire/2001/12/13/jdl/index.html -- Salon Magazine report on the December 12, 2001 charges.