WASHINGTON — Early on Monday evening, Channel 2’s credible correspondent Udi Segal reported that he had been briefed by a senior American intelligence official to the effect that Israel has already made up its mind to attack Iran – unless there is a significant change in the Iranian nuclear drive in the coming weeks and months.

Sources in Netanyahu’s circle swiftly rubbished the notion, describing the story, with its doomsday predictions of regional and even world war, as a “scare tactic” – part of an effort by some in the American hierarchy to tie Israel’s hands.

Listening to Prime Minister Benjamin Netanyahu speaking to AIPAC later on Monday night, however, one could easily imagine that here was a leader whose mind was indeed made up, or very close to it, about the imminent imperative to act decisively to thwart Iran. The Channel 2 story, in the context of the prime minister’s strident remarks, did not sound risible at all.

No one, Netanyahu told the vast audience, could afford to wait much longer. Sanctions were not working. And a nuclear Iran was an intolerable danger.

Netanyahu invoked the Holocaust – at some length. He recalled how the Allies had failed to attack the railway lines to Auschwitz at the height of World War II’s Nazi genocide, and how the Jewish people had been powerless. But 2012 was not 1944, he said. The difference was that, today, there is a state of Israel. “And the purpose of the Jewish state is to defend Jewish lives and to secure the Jewish future.”

“Never again,” he said, using those most potent of words – never again would the Jewish people be powerless. His voice, uncharacteristically, almost broke at this point.

Netanyahu has been accused by his critics over the years of being disingenuous, of being a master of manipulation, of making articulate presentations with little substance behind them. In this speech, he did not sound like he was being manipulative. He sounded like a man who feels the weight of obligation to protect the Jewish people from another genocidal regime. And as long as I am prime minister, he said, “I will never let my people live in the shadow of annihilation.”

It is anyone’s guess what the regime in Tehran will make of this address. For its part, the US administration will have heard almost nothing in it to suggest that the prime minister is in patient mode, prepared to heed President Barack Obama’s appeal, delivered in this same venue on Sunday, to give a little more time for diplomacy and sanctions to have their impact.

The audience, certainly, went away convinced that here is an Israeli prime minister who not only reserves the right to protect his nation as he sees fit, but is getting very close to acting on that right.

The US intelligence official who reportedly briefed Udi Segal lamented that the Israeli public is unaware of the disaster its leadership is on the point of provoking via a strike on Iran’s nuclear facilities. The missiles will rain down in their thousands, the official purportedly said, and the death toll will be in the thousands too. It is “tantamount to suicide,” the official warned.

Netanyahu on Monday night powerfully asserted the right of the Jewish people, for the Jewish state, to fight if necessary for its survival. He did not sound suicidal. But he did sound like a leader who, if he hasn’t completely made up his mind about how and when to act in order to thwart Iran’s nuclear drive, is on the point of taking precisely such a decision.

“There’s been a lot of talk about the cost of stopping Iran,” he said in one of the speech’s most telling passages. “It’s about time we started talking about the cost of not stopping Iran.”