By 2001, Saddam Hussein was more of an unwitting ally of Israel, than an enemy of it.
He supported the Palestinians against Israel, and unlike Iran, which has been waging a proxy war against Israel since the 1980s through Hezbulla and to a lesser extent through Amal, Saddam had the Iraqi army overtly fire rockets that hit Israel, but those days were a decade gone, and nearly as forgotten as the 1980-1988 Iran-Iraq war, in which he was more of a US proxy than the Soviet proxy which he was later forced to be reverted to.
Saddam's Iraq was also in good relations with Jordan, which until that time (Intifadatil Al-Aqsa) had the best relations with Israel, relative to the rest of its neighbors, and this includes Egypt, which had a peace treaty with Israel more than a dozen years prior to Jordan.
Hussein Bin Talal, the King of Jordan until 1999 even warned Israel prior to the combined Arab attack upon it in 1973, in which he also sent the Jordanian 40th armored brigade to help Syria, two decades prior to signing an official peace treaty with Israel.
WMDs or not, Saddam had WMDs when his senior officer, Ali A.K.A."The Chemical" used poison gas/es against the Kurds during Saddam's reign, and I heard that the US supplied him with these WMDs, so how could not it know that he had them?
By the time in which he was forcefully dethroned by the US, very few would argue that Saddam's Iraq was a threat to Israel.
The 2001 attack on Iraq was not a Zionist operation, it was a Wall-Street operation, and you are welcomed to comment to try to show otherwise.