In early January 2002, four months after the September 11 attacks, Israeli national security council director Uzi Dayan met in Washington with his American counterpart Condoleezza Rice. She told him — to his surprise, he later told me — that President Bush had decided to invade Iraq and topple Saddam Hussein. A month later Dayan’s boss, Prime Minister Ariel Sharon, met with Bush in the White House and offered some advice, based on decades of Israeli intelligence.

Removing Saddam, Sharon said, according to three sources with direct knowledge, will have three main results, all negative. Iraq will implode into warring tribes of Sunnis, Shiites and Kurds. You’ll be stuck in an Iraqi quagmire for a decade. And Iran, a far more dangerous player, will be rid of its principal enemy and free to pursue its ambitions of regional hegemony. Bush didn’t agree.

Israeli leaders continued pooh-poohing Iraq all spring. Dismissal turned to alarm in August, when Iranian dissidents released evidence that Iran was pursuing nuclear weapons. In September Sharon told his cabinet to stop discussing Iraq. It was annoying the White House.

On September 12, however, a different Israeli voice visited Washington: ex-prime minister-turned-private citizen Benjamin Netanyahu. A longtime Sharon rival, closely allied with Washington’s neoconservatives, he’d been invited to address the Republican-led House as an expert on Iraq. Baghdad, he said, was hiding mobile centrifuges “the size of washing machines.” Moreover, “if you take out Saddam, Saddam’s regime, I guarantee that it will have enormous positive reverberations on the region.” Throughout the Middle East, including Iran, populations will be inspired to topple their own dictators.

Bush, of course, listened to Netanyahu and the neocons, not Sharon and his generals. Alas, Sharon was right. Iraq imploded. Iran surged. The invasion had reverberations, but hardly positive. The rest is history.