Israel's greatest sporting triumph might be Gal Fridman's Olympic gold in 2004, the country's first and only such medal. But that came in sailing... and, honestly, no one gives a rat's behind about sailing. Sorry, Gal.
So if we ignore sailing (or, perhaps, if we stick to team sports), Israel's greatest sporting triumph just might be the 1977 European Champions Cup in Basketball. (That's a mouthful, so it was renamed the EuroLeague in the years since.) It's the top competition for basketball clubs in Europe, equal to soccer's Champions League.
In 1977, Maccabi Tel Aviv made it to the semifinal stage of the competition, where they faced the heavily favored CSKA Moscow. The Soviets refused to travel to Israel, so the game was played in Belgium instead. The Israelis surprisingly triumphed, and then upset Italians in the title game to claim the unexpected championship.
Maccabi's captain and best player was Tal Brody. Once a top player at the University of Illinois, he was drafted by the NBA's Washington Bullets, but elected to play in Israel. There, he is forever known as "Mr. Basketball" (a better nickname than "Hebrew Hammer", that's for sure). But Brody wasn't originally from Israel... he was born in New Jersey.
Yes, Israel's greatest sporting triumph was due to a Jew from New Jersey. Sorry, Gal.