The Israeli air strike carried out on 07 June 1981, took the world by surprise. It was completely unexpected. Although the planning had gone on for over a year, the secret had somehow been kept from everyone!
Iraq had purchased an Osiris-class nuclear reactor (Osirak) from France in 1976. While both the French and Saddam Hussein claimed the reactor was for "peaceful scientific research" Israel did not buy into the lie.
Apparently Iran didn't either, because they tried to destroy the reactor (and failed) just months before the strike by Israel. The nuclear reactor was under construction 17 kilometers (10.5 miles) southeast of Baghdad, Iraq.
After every attempt to stop Iraq's building a nuclear bomb failed, Israel decided to take defensive action on its own. On 07 June 1981, eight Israeli Air Force fighter aircraft bombed and heavily damaged the Osirak reactor.
With almost flawless execution the strike was timed to minimize casualties and only target the dome of the main reactor. Indeed, only ten Iraqi soldiers and one French civilian were killed. The buildings surrounding the reactor were not damaged. While the world initially condemned Israel (as usual) it was later acknowledged that there was great relief that Israel had acted.
One of the mission pilots was Ilan Ramon who later perished in the Space Shuttle Columbia on 01 February 2003.
Here is the story, as told by those who participated...
Operation Opera (Hebrew: אופרה)07 June 1981