The JDL is now defunct. It has been for a while. That group used to bomb Soviet property in New York to bring attention to the plight of Jews stuck in the USSR. The bombings were usually against property, except for the tear gassing of the Soviet ballet. They never set out to kill people.
JTF is run by Chaim Ben Pesach, who used to run the JDL. We are a law abiding organization of both Jews and righteous gentiles. Our objective is to prevent Israel from giving up any more land to the moosies, and to have a Torah true government there.
In America, our aim to to prevent the election of B. Hussein Obama as our next President, hence the blog and website Jews Against Obama.
Hope that helps.